This past weekend I attended the 20th Association of Chiropractic Colleges meeting, which as always was combined with the Research Agenda Conference, now in its 15th year; the last 9 years have held a combined conference. As always, the conference brings together researchers, academics, administrators and practitioners to share ideas that look at both teaching and research. This year was no different.
The open plenary session started with a presentation by Dr. Norton Hadler, a prominent professor of medicine and microbiology/immunology at University of North Caroline. Dr. Hadler is author of many books, the latest of which are “Worried Sick: A Prescription for Health in an Overtreated American” and “Stabbed in the Back: Confronting Back Pain in an Overtreated Society.” His discussion looked at the personal, social and policy implications of low back pain, noting the impact it has on our lives and yet how little we know for how much we spend looking at it. He was followed by the Dr. Georges Benjamin, the executive director for the American Public Health Association, which he has led since 2002. Dr. Benjamin is a long-time friend of the chiropractic profession, and he led the audience through an overview of how we can help improve population health, asking us to work to involve more of our profession in the public health movement. The final speakers of the morning were Drs. Scott Haldeman, Pierre Cote and Don Murphy, who looked at how our understanding of the purported role of manipulation and stroke is changing as we gather more evidence and show that stroke after manipulation in incredibly rare. We all know Dr. Haldeman, but Dr. Cote is a DC, PHD working at Toronto Western Research Institute and Toronto Western Hospital, while Dr. Murphy is a chiropractor who has assignment at the Albert Medical School of Brown University.
Workshops at ACCRAC included a discussion of back and spinal pain as it relates to public health, a session on the role of ethics in research (near and dear to my heart, but could have been better, just saying), and ones on understanding and implementing boundaries in college and practice, strategies for teaching and assessing clinical reasoning, understanding evidence-based practice, trends in supporting a transition from clinician to educator, taking care of geriatric patients, applying management tools to streamline work efforts in colleges, and accessing the chiropractic literature. We also had a session that looked at the advances made in several of the chiropractic colleges that have received an R25 award. Ours was presented by Dr. Cynthia Long.
Throughout the course of the program paper sessions presented new research to attendees. We were well represented in that effort by papers from Palmer faculty, including Bob Cooperstein, Morgan Young, Makani Lew (all PCCW), Todd Hubbard, Lisa Killinger, Rita Nafziger, Michelle Barber, Maria Anderson (PCCD),Christopher Meseke, Niu Zhang, Xiaohua He, Kim Keene, Anne Canty (PCCF). Palmer faculty and administration were involved in several of the workshops, including Lisa Killinger, Judy Silvestrone, Robert Percuoco, Phyllis Harvey and Cynthia Long. And many Palmer faculty had posters at the program, including Ron Boesch, Bob Cooperstein, Casey Crisp, Todd Hubbard, Stephen Grand, Kenice Morehouse, Dave Juehring, Mike Tunning, Barbara Mansholt, myself, Katherine Pohlman, Maria Hondras, Cynthia Long, Andrea Haan, Dewan Raja, Bahar Sultana, Hong Yu and Xiaohua He. All told, our college was incredibly well represented. We should be proud, and if you see any of the presenters here, give ‘em a pat on the back.
I am proud to say that 2 Palmer papers won prizes given by the National Board of Chiropractic Examiners, one by Niu Zhang and Xiaohua He ("Understanding the intrigue of extraocular muscles and Oculomotor, Trochlear and Abducens nerves through physcial examination: an innovative approach"), and one by Rita Nafziger, Christopher Meseke and Jamie Meseke ("Collaborative testing: the effect of group formation process on overall student performance"). Only 9 total prizes were awarded and we won 2 of them.
Next year’s session has as its general theme “integration.” A new call for papers will be out soon, with a new deadline of late August of this year, so time is already close at hand. Please think about going; it is a fertile arena with which to share ideas and well worth attending.
Monday, March 22, 2010
Monday, March 15, 2010
More New Articles of Interest
Reading through the journals on Biomed Central, I always find new and interesting articles, and wish to share abstracts of several of them with you.
1. Bronfort G, Haas M, Evans R, Leiniger B, Triano J. Effectiveness of manual therapies: the UK evidence report Chiropr Osteop 2010;18:3 doi:10.1186/1746-1340-18-3
Abstract
Background: The purpose of this report is to provide a succinct but comprehensive summary of the scientific evidence regarding the effectiveness of manual treatment for the management of a variety of musculoskeletal and non-musculoskeletal conditions.
Methods: The conclusions are based on the results of systematic reviews of randomized clinical trials (RCTs), widely accepted and primarily UK and United States evidence-based clinical guidelines, plus the results of all RCTs not yet included in the first three categories. The strength/quality of the evidence regarding effectiveness was based on an adapted version of the grading system developed by the US Preventive Services Task Force and a study risk of bias assessment tool for the recent RCTs.
Results: By September 2009, 26 categories of conditions were located containing RCT evidence for the use of manual therapy: 13 musculoskeletal conditions, four types of chronic headache and nine non-musculoskeletal conditions. We identified 49 recent relevant systematic reviews and 16 evidence-based clinical guidelines plus an additional 46 RCTs not yet included in systematic reviews and guidelines. Additionally, brief references are made to other effective non-pharmacological, non-invasive physical treatments.
Conclusions: Spinal manipulation/mobilization is effective in adults for: acute, subacute, and chronic low back pain; migraine and cervicogenic headache; cervicogenic dizziness; manipulation/mobilization is effective for several extremity joint conditions; and thoracic manipulation/mobilization is effective for acute/subacute neck pain. The evidence is inconclusive for cervical manipulation/mobilization alone for neck pain of any duration, and for manipulation/mobilization for mid back pain, sciatica, tension-type headache, coccydynia, temporomandibular joint disorders, fibromyalgia, premenstrual syndrome, and pneumonia in older adults. Spinal manipulation is not effective for asthma and dysmenorrhea when compared to sham manipulation, or for Stage 1 hypertension when added to an antihypertensive diet. In children, the evidence is inconclusive regarding the effectiveness for otitis media and enuresis, and it is not effective for infantile colic and asthma when compared to sham manipulation. Massage is effective in adults for chronic low back pain and chronic neck pain. The evidence is inconclusive for knee osteoarthritis, fibromyalgia, myofascial pain syndrome, migraine headache, and premenstrual syndrome. In children, the evidence is inconclusive for asthma and infantile colic.
2. Myburgh C, Roessler KK, Larsen AH, Hartvigsen J. Neck pain and anxiety do not always go together. Chiropr Osteop 2010;18:6 doi:10.1186/1746-1340-18-6
Abstract
Chronic pain and psychosocial distress are generally thought to be associated in chronic musculoskeletal disorders such as non-specific neck and back pain. However, it is unclear whether a raised level of anxiety is necessarily a feature of longstanding, intense pain amongst patient and general population sub-groups. In a cohort of 70 self-selected female, non-specific neck pain sufferers, we observed relatively high levels of self-reported pain of 4.46 (measured on the 11 point numerical pain rating scale (NRS-101)) and a longstanding duration of symptoms (156 days/year). However, the mean anxiety scores observed (5.49), fell well below the clinically relevant threshold of 21 required by the Beck Anxiety Inventory. The cohort was stratified to further distinguish individuals with higher pain intensity (NRS>6) and longer symptom duration (>90 days). A highly statistically significant difference (p=0.000) was observed with respect to pain intensity. However, no significant differences were noted in the sub-groups with respect to anxiety levels. Our results indicate that chronic, intense pain and anxiety do not always appear to be related. Explanations for these findings may include that anxiety is not triggered in socially functional individuals, that individual coping strategies have come into play or in some instances that a psychological disorder like alexithymia could be a confounder. More studies are needed to clarify the specific role of anxiety in chronic non-specific musculoskeletal pain before general evidence-driven clinical extrapolations can be made.
3. Watmough S, O’Sullivan H, Taylor D. Graduates from a traditional medical curriculum evaluate the effectiveness of their medical curriculum through interviews. BMC Med Educ 2009;9:64 doi:10.1186/1472-6920-9-64
Abstract
Background: In 1996 The University of Liverpool reformed its medical course from a traditional lecture-based course to an integrated PBL curriculum. A project has been underway since 2000 to evaluate this change. Part of this project has involved gathering retrospective views on the relevance of both types of undergraduate education according to graduates. This paper focuses on the views of traditional Liverpool graduates approximately 6 years after graduation.
Methods: From February 2006 to June 2006 interviews took place with 46 graduates from the last 2 cohorts to graduate from the traditional Liverpool curriculum.
Results: The graduates were generally happy with their undergraduate education although they did feel there were some flaws in their curriculum. They felt they had picked up good history and examination skills and were content with their exposure to different specialties on clinical attachments. They were also pleased with their basic science teaching as preparation for postgraduate exams, however many complained about the overload and irrelevance of many lectures in the early years of their course, particular in biochemistry. There were many different views about how they integrated this science teaching into understanding disease processes and many didn't feel it was made relevant to them at the time they learned it. Retrospectively, they felt that they hadn't been clinically well prepared for the role of working as junior doctor, particularly the practical aspects of the job nor had enough exposure to research skills. Although there was little communication skills training in their course they didn't feel they would have benefited from this training as they managed to pick up had the required skills on clinical attachments.
Conclusion: These interviews offer a historical snapshot of the views of graduates from a traditional course before many courses were reformed. There was some conflict in the interviews about the doctors enjoying their undergraduate education but then saying that they didn't feel they received good preparation for working as a junior doctor. Although the graduates were happy with their undergraduate education these interviews do highlight some of the reasons why the traditional curriculum was reformed at Liverpool
1. Bronfort G, Haas M, Evans R, Leiniger B, Triano J. Effectiveness of manual therapies: the UK evidence report Chiropr Osteop 2010;18:3 doi:10.1186/1746-1340-18-3
Abstract
Background: The purpose of this report is to provide a succinct but comprehensive summary of the scientific evidence regarding the effectiveness of manual treatment for the management of a variety of musculoskeletal and non-musculoskeletal conditions.
Methods: The conclusions are based on the results of systematic reviews of randomized clinical trials (RCTs), widely accepted and primarily UK and United States evidence-based clinical guidelines, plus the results of all RCTs not yet included in the first three categories. The strength/quality of the evidence regarding effectiveness was based on an adapted version of the grading system developed by the US Preventive Services Task Force and a study risk of bias assessment tool for the recent RCTs.
Results: By September 2009, 26 categories of conditions were located containing RCT evidence for the use of manual therapy: 13 musculoskeletal conditions, four types of chronic headache and nine non-musculoskeletal conditions. We identified 49 recent relevant systematic reviews and 16 evidence-based clinical guidelines plus an additional 46 RCTs not yet included in systematic reviews and guidelines. Additionally, brief references are made to other effective non-pharmacological, non-invasive physical treatments.
Conclusions: Spinal manipulation/mobilization is effective in adults for: acute, subacute, and chronic low back pain; migraine and cervicogenic headache; cervicogenic dizziness; manipulation/mobilization is effective for several extremity joint conditions; and thoracic manipulation/mobilization is effective for acute/subacute neck pain. The evidence is inconclusive for cervical manipulation/mobilization alone for neck pain of any duration, and for manipulation/mobilization for mid back pain, sciatica, tension-type headache, coccydynia, temporomandibular joint disorders, fibromyalgia, premenstrual syndrome, and pneumonia in older adults. Spinal manipulation is not effective for asthma and dysmenorrhea when compared to sham manipulation, or for Stage 1 hypertension when added to an antihypertensive diet. In children, the evidence is inconclusive regarding the effectiveness for otitis media and enuresis, and it is not effective for infantile colic and asthma when compared to sham manipulation. Massage is effective in adults for chronic low back pain and chronic neck pain. The evidence is inconclusive for knee osteoarthritis, fibromyalgia, myofascial pain syndrome, migraine headache, and premenstrual syndrome. In children, the evidence is inconclusive for asthma and infantile colic.
2. Myburgh C, Roessler KK, Larsen AH, Hartvigsen J. Neck pain and anxiety do not always go together. Chiropr Osteop 2010;18:6 doi:10.1186/1746-1340-18-6
Abstract
Chronic pain and psychosocial distress are generally thought to be associated in chronic musculoskeletal disorders such as non-specific neck and back pain. However, it is unclear whether a raised level of anxiety is necessarily a feature of longstanding, intense pain amongst patient and general population sub-groups. In a cohort of 70 self-selected female, non-specific neck pain sufferers, we observed relatively high levels of self-reported pain of 4.46 (measured on the 11 point numerical pain rating scale (NRS-101)) and a longstanding duration of symptoms (156 days/year). However, the mean anxiety scores observed (5.49), fell well below the clinically relevant threshold of 21 required by the Beck Anxiety Inventory. The cohort was stratified to further distinguish individuals with higher pain intensity (NRS>6) and longer symptom duration (>90 days). A highly statistically significant difference (p=0.000) was observed with respect to pain intensity. However, no significant differences were noted in the sub-groups with respect to anxiety levels. Our results indicate that chronic, intense pain and anxiety do not always appear to be related. Explanations for these findings may include that anxiety is not triggered in socially functional individuals, that individual coping strategies have come into play or in some instances that a psychological disorder like alexithymia could be a confounder. More studies are needed to clarify the specific role of anxiety in chronic non-specific musculoskeletal pain before general evidence-driven clinical extrapolations can be made.
3. Watmough S, O’Sullivan H, Taylor D. Graduates from a traditional medical curriculum evaluate the effectiveness of their medical curriculum through interviews. BMC Med Educ 2009;9:64 doi:10.1186/1472-6920-9-64
Abstract
Background: In 1996 The University of Liverpool reformed its medical course from a traditional lecture-based course to an integrated PBL curriculum. A project has been underway since 2000 to evaluate this change. Part of this project has involved gathering retrospective views on the relevance of both types of undergraduate education according to graduates. This paper focuses on the views of traditional Liverpool graduates approximately 6 years after graduation.
Methods: From February 2006 to June 2006 interviews took place with 46 graduates from the last 2 cohorts to graduate from the traditional Liverpool curriculum.
Results: The graduates were generally happy with their undergraduate education although they did feel there were some flaws in their curriculum. They felt they had picked up good history and examination skills and were content with their exposure to different specialties on clinical attachments. They were also pleased with their basic science teaching as preparation for postgraduate exams, however many complained about the overload and irrelevance of many lectures in the early years of their course, particular in biochemistry. There were many different views about how they integrated this science teaching into understanding disease processes and many didn't feel it was made relevant to them at the time they learned it. Retrospectively, they felt that they hadn't been clinically well prepared for the role of working as junior doctor, particularly the practical aspects of the job nor had enough exposure to research skills. Although there was little communication skills training in their course they didn't feel they would have benefited from this training as they managed to pick up had the required skills on clinical attachments.
Conclusion: These interviews offer a historical snapshot of the views of graduates from a traditional course before many courses were reformed. There was some conflict in the interviews about the doctors enjoying their undergraduate education but then saying that they didn't feel they received good preparation for working as a junior doctor. Although the graduates were happy with their undergraduate education these interviews do highlight some of the reasons why the traditional curriculum was reformed at Liverpool
Monday, March 8, 2010
And the Beginning of a New Term; Three Ethics Scenarios
I think that at times there is some confusion in separating out research ethics from clinical ethics. In the case of the latter, we are referring specifically to the ethics of patient care when patients seek care from a physician for a problem that they have. In such cases, it is assumed that the physician will do everything in his or her power to help the patient get better. A physician might try a particular drug, or perhaps a particular adjusting technique, and if that does not work, he or she might try something completely different. In research ethics, as contrast, the main goal is to obtain generalizable information, and in such cases researchers are constrained by the protocols of their study. Which means that they might not be able to try all possible avenues or interventions for their patient. All too often, neither patient nor researcher really understands this. And this is but one small point of difference. Just to illustrate some of the challenges in bioethics, I offer here a few scenaries, without providing any answer or resolution to them, just to give you an idea of the complexities I mentioned above.
Scenario 1: You have developed a new method of treating patients suffering from Alzheimer’s disease. You wish to compare your intervention to an established method of treating this debilitating and distressing condition, and the best way to do so is to conduct a two-arm clinical trial, randomizing treatment into one of two treatment groups (your method or the established method). However, you are well aware that you must receive informed consent from the patient, yet many of the patients are not lucid or have, at best, periods of lucidity. How should you proceed with obtaining consent?
Scenario 2: Professor Allan Sundry is the course director of a physiology laboratory taught to chiropractic students. One of the laboratory exercises involves students’ drawing blood from one another (under supervision) and using the serum to perform a variety of chemical and cellular analyses. The lab exercise is carried out successfully. At its conclusion Professor Sundry announces to the class of 50 students that he would like to retain their leftover blood sera. He informs them some of the sera will be used individually while some will be pooled. In all cases these sera will be used to gather baseline control data in a number of research projects. He asks if anyone wants to refuse having his or her serum used for research but receives no objections. Are Allan’s actions appropriate? Is an IRB-approved protocol needed? Do the students need to give informed consent?
Scenario 3: You have submitted a new paper to a reputable journal in which you present some exciting data based on a technology you are in the forefront of developing. A number of weeks go by and you do not hear anything from the journal, so you contact the editor to find out why. He tells you that the paper is still in review and the one reviewer has yet to return a completed review. Shortly after, you see a new paper in a different journal, and it contains information that can only have come from your paper. What ethical transgressions may have occurred and what should you do?
Think about how you might respond to each of these scenarios…
Scenario 1: You have developed a new method of treating patients suffering from Alzheimer’s disease. You wish to compare your intervention to an established method of treating this debilitating and distressing condition, and the best way to do so is to conduct a two-arm clinical trial, randomizing treatment into one of two treatment groups (your method or the established method). However, you are well aware that you must receive informed consent from the patient, yet many of the patients are not lucid or have, at best, periods of lucidity. How should you proceed with obtaining consent?
Scenario 2: Professor Allan Sundry is the course director of a physiology laboratory taught to chiropractic students. One of the laboratory exercises involves students’ drawing blood from one another (under supervision) and using the serum to perform a variety of chemical and cellular analyses. The lab exercise is carried out successfully. At its conclusion Professor Sundry announces to the class of 50 students that he would like to retain their leftover blood sera. He informs them some of the sera will be used individually while some will be pooled. In all cases these sera will be used to gather baseline control data in a number of research projects. He asks if anyone wants to refuse having his or her serum used for research but receives no objections. Are Allan’s actions appropriate? Is an IRB-approved protocol needed? Do the students need to give informed consent?
Scenario 3: You have submitted a new paper to a reputable journal in which you present some exciting data based on a technology you are in the forefront of developing. A number of weeks go by and you do not hear anything from the journal, so you contact the editor to find out why. He tells you that the paper is still in review and the one reviewer has yet to return a completed review. Shortly after, you see a new paper in a different journal, and it contains information that can only have come from your paper. What ethical transgressions may have occurred and what should you do?
Think about how you might respond to each of these scenarios…
Monday, March 1, 2010
More Cultural Memes- The End of Another Term...
Meme: “a cultural unit (an idea or value or pattern of behavior) that is passed from one person to another by non-genetic means (as by imitation).”
As the Davenport campus heads to a between-terms break, herewith are a number of interesting, intriguing and just sheer fun youtube clips, of no special relation to education or anything else. I’ll be back posting on related topics on March 9, after we complete the Davenport in-service day.
1. Paul Potts sings “Nessum Dorma” on Britain’s You’ve Got Talent: Okay, he’s overweight, his shirt isn’t tucked in, and his teeth need serious work, but when he begins singing, the judges (which include American Idol’s Simon Cowell) are thunderstruck. This clip is worth it just to see Cowell take note about 4 seconds after Potts starts singing. This has been seen more than 60 million times and the crowd reaction at the end is priceless. http://www.youtube.com/watch?v=1k08yxu57NA
2. Surprised Kitty- this is a cultural phenomenon. How this entered into cultural memory isn’t well understood, but the clip has been seen more than 20 million times now. You can’t watch and not smile at it. http://www.youtube.com/watch?v=0Bmhjf0rKe8&feature=related
3. “Bear Grylls is a phony.” I love Man vs. Wild, but Bear isn’t always showing the whole picture. And maybe we can understand why, watching this clip- which slowly shows that the crevice isn’t really a crevice and he’s not maybe so out in the wild… http://www.youtube.com/watch?v=3UpSlpvb1is
4. Franz Klammer, Innsbruck 1976: Over the past week we have seen wonderful races from Lindsey Vonn, Julia Mancuso and Bode Miller, but the greatest single downhill race of all time was Klammer’s race in the 1976 Olympics, when he ran the course at the very edges of sanity, nearly losing control several times, but managing to pull out an amazing gold medal run. http://www.youtube.com/watch?v=tVMJKIx34SE&feature=related
5. Usain Bolt breaks the world record in the 200m sprint: At the 2009 Berlin World Championships, Bolt set new records in the 100m and 200m races that will likely not be broken for a decade, unless he himself breaks them. In a sport where records improve in increments of a hundredth of a second, he knocked more than a tenth of a second off the 100m record and even more than that in the 200m. Against the fastest men in the world, look how much he wins by in over just 200m. http://www.youtube.com/watch?v=_DjvvI-0xjc&feature=related
6. The Beatles on Ed Sullivan, 1964: If you have to ask, you weren’t there. If you were there, this is indelible in your mind. A cultural benchmark. http://www.youtube.com/watch?v=-DvbDZihKwI
7. That’s all, folks! http://www.youtube.com/watch?v=gBzJGckMYO4
See you soon!
As the Davenport campus heads to a between-terms break, herewith are a number of interesting, intriguing and just sheer fun youtube clips, of no special relation to education or anything else. I’ll be back posting on related topics on March 9, after we complete the Davenport in-service day.
1. Paul Potts sings “Nessum Dorma” on Britain’s You’ve Got Talent: Okay, he’s overweight, his shirt isn’t tucked in, and his teeth need serious work, but when he begins singing, the judges (which include American Idol’s Simon Cowell) are thunderstruck. This clip is worth it just to see Cowell take note about 4 seconds after Potts starts singing. This has been seen more than 60 million times and the crowd reaction at the end is priceless. http://www.youtube.com/watch?v=1k08yxu57NA
2. Surprised Kitty- this is a cultural phenomenon. How this entered into cultural memory isn’t well understood, but the clip has been seen more than 20 million times now. You can’t watch and not smile at it. http://www.youtube.com/watch?v=0Bmhjf0rKe8&feature=related
3. “Bear Grylls is a phony.” I love Man vs. Wild, but Bear isn’t always showing the whole picture. And maybe we can understand why, watching this clip- which slowly shows that the crevice isn’t really a crevice and he’s not maybe so out in the wild… http://www.youtube.com/watch?v=3UpSlpvb1is
4. Franz Klammer, Innsbruck 1976: Over the past week we have seen wonderful races from Lindsey Vonn, Julia Mancuso and Bode Miller, but the greatest single downhill race of all time was Klammer’s race in the 1976 Olympics, when he ran the course at the very edges of sanity, nearly losing control several times, but managing to pull out an amazing gold medal run. http://www.youtube.com/watch?v=tVMJKIx34SE&feature=related
5. Usain Bolt breaks the world record in the 200m sprint: At the 2009 Berlin World Championships, Bolt set new records in the 100m and 200m races that will likely not be broken for a decade, unless he himself breaks them. In a sport where records improve in increments of a hundredth of a second, he knocked more than a tenth of a second off the 100m record and even more than that in the 200m. Against the fastest men in the world, look how much he wins by in over just 200m. http://www.youtube.com/watch?v=_DjvvI-0xjc&feature=related
6. The Beatles on Ed Sullivan, 1964: If you have to ask, you weren’t there. If you were there, this is indelible in your mind. A cultural benchmark. http://www.youtube.com/watch?v=-DvbDZihKwI
7. That’s all, folks! http://www.youtube.com/watch?v=gBzJGckMYO4
See you soon!
Tuesday, February 23, 2010
Survey Development: Continuous Judgments and Direct Estimation Methods
Many of us develop surveys for use in classroom or clinical settings. When we do, we have to consider the variables that we are interested in, and often we find that these are continuous rather than categorical. One method of collecting continuous data is via a direct estimation method, where subjects are required to indicate their response by a mark on a line or by checking a box. One example of such a method would be a visual analogue scale for pain: a line of 10cm anchored with descriptors at one end of “no pain” and at the other with “worst pain imaginable.” But if you think about it, you could ask this question using different means of collecting the data. For example, you could offer the subject a series of choices, such as boxes with these descriptors: no pain, minor pain, moderate pain, severe pain, worst pain. This adjectival scale gives 5 choices from which to select. This is also called a unipolar scale, in that the descriptors range from no or little of the attribute at one end to the maximal amount at the other. This is in contrast to the Likert scale, which is bipolar, which means that it is often used to tap agreement (i.e., strongly disagree, disagree, no opinion, agree, strongly agree). But the choice of a proper scale for a question is important, both for continuous variables or categorical/dichotomous ones.
These are some of the issues you should consider when constructing a survey which uses continuous scaling:
1. How many steps should there be? This is an important consideration; if the number of levels is less than the participant’s ability to discriminate, the results will be a loss of information. Research on this question is unclear, but suggests that 5-7 steps seems to provide best information with little loss of reliability.
2. Is there a maximum number of categories? There seems to be some evidence that people cannot discriminate beyond 7 levels. But keep in mind that it is also known that people have “end aversion,” meaning that they typically avoid the end points of any scale.
3. Should there be an even or odd number of categories? For a unipolar scale, this would not matter, but for a bipolar scale the use of an odd number allows you to build in a “no opinion” option.
4. Should all the points on a scale be labeled, or only the ends? While research indicates that there is relatively little difference between scale with adjectives under each box and end-anchored scales, that same research indicates that respondents are more satisfied when many or all the points on a scale are labeled. Also, if you do not label all boxes, research has shown that people will often select a box that has been labeled, not one that has not.
5. Should the neutral point always be in the middle? Where positive or negative responses to an item are equally possible, it makes sense to have the neutral point in the middle. There are more technical reasons to unbalance a scale but I will not describe them here.
6. Do the adjectives always convey the same meaning? What does it mean to agree or to strongly agree? How does “often” differ from “not too often?” The use of these quantifiers requires care and consideration.
7. Do numbers placed under the boxes influence response? Yes, to be direct. When a set of VAS scales were used in one study, with the only difference being that one scale ran from 0-10 and the other from -5 to +5, a much higher percentage of respondents did not use the lower half of the scale in the latter group (87%), while 34% of the first group did use it.
8. Do questions influence the response to other questions? Yes. People wish to seem consistent and will often refer back to questions when answering new ones. Also, participants often try to interpret what the question is asking them, so they can respond appropriately.
The take home message from all this is that it is very hard to develop good questions in surveys and a great deal of thought and testing needs to go into testing the questions you write before you use them in survey research. This is but a small part of information on this topic, but my reference for this is from the following book: Streiner DL, Norman GR. Health measurement scales: a practical guide to their development and use, 3rd edition. New York City, NY; Oxford Press, 2003.
These are some of the issues you should consider when constructing a survey which uses continuous scaling:
1. How many steps should there be? This is an important consideration; if the number of levels is less than the participant’s ability to discriminate, the results will be a loss of information. Research on this question is unclear, but suggests that 5-7 steps seems to provide best information with little loss of reliability.
2. Is there a maximum number of categories? There seems to be some evidence that people cannot discriminate beyond 7 levels. But keep in mind that it is also known that people have “end aversion,” meaning that they typically avoid the end points of any scale.
3. Should there be an even or odd number of categories? For a unipolar scale, this would not matter, but for a bipolar scale the use of an odd number allows you to build in a “no opinion” option.
4. Should all the points on a scale be labeled, or only the ends? While research indicates that there is relatively little difference between scale with adjectives under each box and end-anchored scales, that same research indicates that respondents are more satisfied when many or all the points on a scale are labeled. Also, if you do not label all boxes, research has shown that people will often select a box that has been labeled, not one that has not.
5. Should the neutral point always be in the middle? Where positive or negative responses to an item are equally possible, it makes sense to have the neutral point in the middle. There are more technical reasons to unbalance a scale but I will not describe them here.
6. Do the adjectives always convey the same meaning? What does it mean to agree or to strongly agree? How does “often” differ from “not too often?” The use of these quantifiers requires care and consideration.
7. Do numbers placed under the boxes influence response? Yes, to be direct. When a set of VAS scales were used in one study, with the only difference being that one scale ran from 0-10 and the other from -5 to +5, a much higher percentage of respondents did not use the lower half of the scale in the latter group (87%), while 34% of the first group did use it.
8. Do questions influence the response to other questions? Yes. People wish to seem consistent and will often refer back to questions when answering new ones. Also, participants often try to interpret what the question is asking them, so they can respond appropriately.
The take home message from all this is that it is very hard to develop good questions in surveys and a great deal of thought and testing needs to go into testing the questions you write before you use them in survey research. This is but a small part of information on this topic, but my reference for this is from the following book: Streiner DL, Norman GR. Health measurement scales: a practical guide to their development and use, 3rd edition. New York City, NY; Oxford Press, 2003.
Monday, February 15, 2010
Promoting Active Member Participation in Group Process Settings
For those of us who use small-group learning processes in the classroom, helping those small groups become effective may involve a number of important considerations. Literature on small-group effectiveness has identified several characteristics that differ between new groups and groups that have existed for some time (1). Among these are:
Group Trust and Attraction: People’s willingness to be attracted to a group (and thereby participate) relates to the level of trust members have in each other. This occurs when members see each other reliably complete tasks over time; thus, newer groups may lack trust that older groups have established. A tactic here would be to provide small tasks at the outset that can be completed, thus beginning to build that trust.
Motivation to Achieve Group Goals: Group goals are seen as a key in the development of group trust and cohesiveness. In groups with high levels of diversity, finding common goals is helpful in developing team identity. Goals also provide a basis for team interaction. Highly cohesive groups are generally more effective at achieving group goals.
Willingness to Help Each Other: Effective groups are generally comprised of people willing to help one another. They fell responsibility toward one another and are more willing to provide interpersonal support.
Awareness of Each Other’s Skills and Abilities: New groups do not yet understand what each member brings to the table, and their perceptions of each other may initially be based on stereotyping and observable physical characteristics. Over time, as they work together, each person’s skills are brought to the fore.
Effective Sharing of Task-Related Information: Information sharing in new groups is not likely to support high task performance on tasks; thus, exchange of task-related information is likely to be low and focused on lower-level learning. Interpersonal issues seem to take precedence. Over time, as groups develop, group members begin to get more comfortable with each other and shift to task-related issues. Long-lived groups have a lessened reliance on their best member.
Willingness to Disagree: Completion of tasks requires some constructive conflict, but new groups generally withhold information that would make such constructive conflict possible. That is, they suppress information that might create conflict in order to maintain harmony at all costs.
Methods of Resolving Conflict: Conflict resolution differs between new small groups and established ones (groups with more than, say, 20 hours of action). For example, voting is often used in new groups to resolve conflict, while consensus emerges as a main conflict resolution process in more established groups.
Overall Ability to Complete Difficult Intellectual Tasks: In new groups, members need to work on tasks while at the same time learn to work with each other. This can lead to some dysfunction, but this dysfunction is also actually useful for the group to later find ways to work out its issues and begin to trust one another. Give-and-take discussions need to occur at some point.
The point of all this is simply to note that you can anticipate certain problems when you first constitute small groups for classroom learning, but that you can also develop tactics and strategies to help smooth the process from new group to established group. This then enhances learning.
References
1. Michaelson LK, Bauman Knight A, Fink LD, eds. Team-based learning: a transformative use of small groups in college teaching. Sterling, VA; Stylus Publishing, 2004
Group Trust and Attraction: People’s willingness to be attracted to a group (and thereby participate) relates to the level of trust members have in each other. This occurs when members see each other reliably complete tasks over time; thus, newer groups may lack trust that older groups have established. A tactic here would be to provide small tasks at the outset that can be completed, thus beginning to build that trust.
Motivation to Achieve Group Goals: Group goals are seen as a key in the development of group trust and cohesiveness. In groups with high levels of diversity, finding common goals is helpful in developing team identity. Goals also provide a basis for team interaction. Highly cohesive groups are generally more effective at achieving group goals.
Willingness to Help Each Other: Effective groups are generally comprised of people willing to help one another. They fell responsibility toward one another and are more willing to provide interpersonal support.
Awareness of Each Other’s Skills and Abilities: New groups do not yet understand what each member brings to the table, and their perceptions of each other may initially be based on stereotyping and observable physical characteristics. Over time, as they work together, each person’s skills are brought to the fore.
Effective Sharing of Task-Related Information: Information sharing in new groups is not likely to support high task performance on tasks; thus, exchange of task-related information is likely to be low and focused on lower-level learning. Interpersonal issues seem to take precedence. Over time, as groups develop, group members begin to get more comfortable with each other and shift to task-related issues. Long-lived groups have a lessened reliance on their best member.
Willingness to Disagree: Completion of tasks requires some constructive conflict, but new groups generally withhold information that would make such constructive conflict possible. That is, they suppress information that might create conflict in order to maintain harmony at all costs.
Methods of Resolving Conflict: Conflict resolution differs between new small groups and established ones (groups with more than, say, 20 hours of action). For example, voting is often used in new groups to resolve conflict, while consensus emerges as a main conflict resolution process in more established groups.
Overall Ability to Complete Difficult Intellectual Tasks: In new groups, members need to work on tasks while at the same time learn to work with each other. This can lead to some dysfunction, but this dysfunction is also actually useful for the group to later find ways to work out its issues and begin to trust one another. Give-and-take discussions need to occur at some point.
The point of all this is simply to note that you can anticipate certain problems when you first constitute small groups for classroom learning, but that you can also develop tactics and strategies to help smooth the process from new group to established group. This then enhances learning.
References
1. Michaelson LK, Bauman Knight A, Fink LD, eds. Team-based learning: a transformative use of small groups in college teaching. Sterling, VA; Stylus Publishing, 2004
Monday, February 8, 2010
A Short Description of Multiple Regression
The context for evidence-based practice revolves around the diagnosis and management of a patient. When a physician is confronted with a patient for whom he or she does not know the best method to proceed, that physician can search the literature to find guidance and direction. One of the challenges of living in a evidence-based world is to be able to then interpret the literature that is uncovered. And because most of us trained as clinical practitioners (for those that are involved in patient care), we do not generally have statistical expertise. We come across terms that confuse us: confidence intervals, p-values, t tests, Pearson’s r, Cronbach’s alpha, linear and multiple regression, analysis of variance (ANOVA), etc. And we simply glitch over those terms, looking to see if our answer is somehow embedded in that paper, but not understanding that answer when it appears. To help, I wish to discuss one form of analysis we often come across: multiple regression.
Multiple regression is nothing more than a statistical method for studying the relationship between several independent or predictor variables and a single dependent or criterion variable. This is a technique widely used in social sciences and increasingly common in biological clinical research. It uses linear equations with more than 2 variables, in the forms y= a + b1x1 + b2x2, where y is the dependent variable, a and b are constant numbers and x1 and x2 are independent variables.
There are two main uses for multiple regression. One is for prediction, and the other is for causal analysis. In prediction studies, what the research is attempting to do is to develop a formula for making predictions about the dependent variable, based on the observed values of the independent variables. (1) (Note: A dependent variable is what you measure in the experiment and what is affected during the experiment. The dependent variable responds to the independent variable. It is called dependent because it "depends" on the independent variable. In a scientific experiment, you cannot have a dependent variable without an independent variable. Further, dependent variables are also called response variables or outcome variables; independent variables may be called predictor variables or explanatory variables). We might, for example, want to predict future episodes of low back pain based on such variables as past episodes of pain, pain intensity, length of episode, and age. In a causal study, the independent variables are seen as the cause of the dependent variable and therefore the aim of the study becomes determining whether a given independent variable affects the dependent variable in a meaningful way, and to estimate how large that effect is. We might have data showing that people who participate in a back school have less severe episodes of later back pain. A multiple regression can determine if this relationship is real or if it could be explained away by the fact that the people who took the back school were younger, fitter and did more exercise than those who did not.
Multiple regression has some truly notable attributes. In prediction studies, it makes it possible to combine variables to optimize predictions about the dependent variable. But, in causal studies it actually separates the effects of independent variables on the dependent variable so you can look at the contribution of each variable on its own.
Some caveats: First, one of the main conceptual problems with regression techniques are that they can ascertain relationships, but cannot be sure about underlying causal mechanisms. Second, the more predictor variables you add to the model, the more likely some will appear to be significant due to chance alone.
References
1. Allison PD. Multiple regression: a primer. Thousand Oaks, CA: Pine Oaks Press, 1999
Multiple regression is nothing more than a statistical method for studying the relationship between several independent or predictor variables and a single dependent or criterion variable. This is a technique widely used in social sciences and increasingly common in biological clinical research. It uses linear equations with more than 2 variables, in the forms y= a + b1x1 + b2x2, where y is the dependent variable, a and b are constant numbers and x1 and x2 are independent variables.
There are two main uses for multiple regression. One is for prediction, and the other is for causal analysis. In prediction studies, what the research is attempting to do is to develop a formula for making predictions about the dependent variable, based on the observed values of the independent variables. (1) (Note: A dependent variable is what you measure in the experiment and what is affected during the experiment. The dependent variable responds to the independent variable. It is called dependent because it "depends" on the independent variable. In a scientific experiment, you cannot have a dependent variable without an independent variable. Further, dependent variables are also called response variables or outcome variables; independent variables may be called predictor variables or explanatory variables). We might, for example, want to predict future episodes of low back pain based on such variables as past episodes of pain, pain intensity, length of episode, and age. In a causal study, the independent variables are seen as the cause of the dependent variable and therefore the aim of the study becomes determining whether a given independent variable affects the dependent variable in a meaningful way, and to estimate how large that effect is. We might have data showing that people who participate in a back school have less severe episodes of later back pain. A multiple regression can determine if this relationship is real or if it could be explained away by the fact that the people who took the back school were younger, fitter and did more exercise than those who did not.
Multiple regression has some truly notable attributes. In prediction studies, it makes it possible to combine variables to optimize predictions about the dependent variable. But, in causal studies it actually separates the effects of independent variables on the dependent variable so you can look at the contribution of each variable on its own.
Some caveats: First, one of the main conceptual problems with regression techniques are that they can ascertain relationships, but cannot be sure about underlying causal mechanisms. Second, the more predictor variables you add to the model, the more likely some will appear to be significant due to chance alone.
References
1. Allison PD. Multiple regression: a primer. Thousand Oaks, CA: Pine Oaks Press, 1999
Subscribe to:
Posts (Atom)
Posts
