Identifying factors likely to influence compliance with diagnostic imaging guideline recommendations for spine disorders among chiropractors in North America: a focus group study using the Theoretical Domains Framework

ABSTRACT: BACKGROUND: The Theoretical Domains Framework (TDF) was developed to investigate determinants of specific clinical behaviors and inform the design of interventions to change professional behavior. This framework was used to explore the beliefs of chiropractors in an American Provider Network and two Canadian provinces about their adherence to evidence-based recommendations for spine radiography for uncomplicated back pain. The primary objective of the study was to identify chiropractors' beliefs about managing uncomplicated back pain without x-rays and to explore barriers and facilitators to implementing evidence-based recommendations on lumbar spine x-rays. A secondary objective was to compare chiropractors in the United States and Canada on their beliefs regarding the use of spine x-rays. METHODS: Six focus groups exploring beliefs about managing back pain without x-rays were conducted with a purposive sample. The interview guide was based upon the TDF. Focus groups were digitally recorded, transcribed verbatim, and analyzed by two independent assessors using thematic content analysis based on the TDF. RESULTS: Five domains were identified as likely relevant. Key beliefs within these domains included the following: conflicting comments about the potential consequences of not ordering x-rays (risk of missing a pathology, avoiding adverse treatment effects, risks of litigation, determining the treatment plan, and using x-ray-driven techniques contrasted with perceived benefits of minimizing patient radiation exposure and reducing costs; beliefs about consequences); beliefs regarding professional autonomy, professional credibility, lack of standardization, and agreement with guidelines widely varied (social/professional role & identity); the influence of formal training, colleagues, and patients also appeared to be important factors (social influences); conflicting comments regarding levels of confidence and comfort in managing patients without x-rays (belief about capabilities); and guideline awareness and agreements (knowledge). CONCLUSIONS: Chiropractors' use of diagnostic imaging appears to be influenced by a number of factors. Five key domains may be important considering the presence of conflicting beliefs, evidence of strong beliefs likely to impact the behavior of interest, and high frequency of beliefs. The results will inform the development of a theory-based survey to help identify potential targets for behavioral-change strategies.     

Anesthesiologists' and surgeons' perceptions about routine pre-operative testing in low-risk patients: application of the Theoretical Domains Framework (TDF) to identify factors that influence physicians' decisions to order pre-operative tests

ABSTRACT: BACKGROUND: Routine pre-operative tests for anesthesia management are often ordered by bothanesthesiologists and surgeons for healthy patients undergoing low-risk surgery. TheTheoretical Domains Framework (TDF) was developed to investigate determinants ofbehaviour and identify potential behaviour change interventions. In this study, the TDF is used to explore anaesthesiologists' and surgeons' perceptions of ordering routine tests forhealthy patients undergoing low-risk surgery. METHODS: Sixteen clinicians (eleven anesthesiologists and five surgeons) throughout Ontario wererecruited. An interview guide based on the TDF was developed to identify beliefs about preoperativetesting practices. Content analysis of physicians' statements into the relevanttheoretical domains was performed. Specific beliefs were identified by grouping similarutterances of the interview participants. Relevant domains were identified by noting thefrequencies of the beliefs reported, presence of conflicting beliefs, and perceived influence onthe performance of the behaviour under investigation. RESULTS: Seven of the twelve domains were identified as likely relevant to changing clinicians'behaviour about pre-operative test ordering for anesthesia management. Key beliefs wereidentified within these domains including: conflicting comments about who was responsiblefor the test-ordering (Social/professional role and identity); inability to cancel tests orderedby fellow physicians (Beliefs about capabilities and social influences); and the problem withtests being completed before the anesthesiologists see the patient (Beliefs about capabilitiesand Environmental context and resources). Often, tests were ordered by an anesthesiologistbased on who may be the attending anesthesiologist on the day of surgery while surgeonsordered tests they thought anesthesiologists may need (Social influences). There were alsoconflicting comments about the potential consequences associated with reducing testing,from negative (delay or cancel patients' surgeries), to indifference (little or no change inpatient outcomes), to positive (save money, avoid unnecessary investigations) (Beliefs aboutconsequences). Further, while most agreed that they are motivated to reduce orderingunnecessary tests (Motivation and goals), there was still a report of a gap between theirmotivation and practice (Behavioural regulation). CONCLUSION: We identified key factors that anesthesiologists and surgeons believe influence whether theyorder pre-operative tests routinely for anesthesia management for a healthy adults undergoinglow-risk surgery. These beliefs identify potential individual, team, and organisation targetsfor behaviour change interventions to reduce unnecessary routine test ordering.     

Improving appropriate polypharmacy for older people in primary care: selecting components of an evidence-based intervention to target prescribing and dispensing

Background

The use of multiple medicines (polypharmacy) is increasingly common in older people. Ensuring that patients receive the most appropriate combinations of medications (appropriate polypharmacy) is a significant challenge. The quality of evidence to support the effectiveness of interventions to improve appropriate polypharmacy is low. Systematic identification of mediators of behaviour change, using the Theoretical Domains Framework (TDF), provides a theoretically robust evidence base to inform intervention design. This study aimed to (1) identify key theoretical domains that were perceived to influence the prescribing and dispensing of appropriate polypharmacy to older patients by general practitioners (GPs) and community pharmacists, and (2) map domains to associated behaviour change techniques (BCTs) to include as components of an intervention to improve appropriate polypharmacy in older people in primary care.

Methods

Semi-structured interviews were conducted with members of each healthcare professional (HCP) group using tailored topic guides based on TDF version 1 (12 domains). Questions covering each domain explored HCPs’ perceptions of barriers and facilitators to ensuring the prescribing and dispensing of appropriate polypharmacy to older people. Interviews were audio-recorded and transcribed verbatim. Data analysis involved the framework method and content analysis. Key domains were identified and mapped to BCTs based on established methods and discussion within the research team.

Results

Thirty HCPs were interviewed (15 GPs, 15 pharmacists). Eight key domains were identified, perceived to influence prescribing and dispensing of appropriate polypharmacy: ‘Skills’, ‘Beliefs about capabilities’, ‘Beliefs about consequences’, ‘Environmental context and resources’, ‘Memory, attention and decision processes’, ‘Social/professional role and identity’, ‘Social influences’ and ‘Behavioural regulation’. Following mapping, four BCTs were selected for inclusion in an intervention for GPs or pharmacists: ‘Action planning’, ‘Prompts/cues’, ‘Modelling or demonstrating of behaviour’ and ‘Salience of consequences’. An additional BCT (‘Social support or encouragement’) was selected for inclusion in a community pharmacy-based intervention in order to address barriers relating to interprofessional working that were encountered by pharmacists.

Conclusions

Selected BCTs will be operationalised in a theory-based intervention to improve appropriate polypharmacy for older people, to be delivered in GP practice and community pharmacy settings. Future research will involve development and feasibility testing of this intervention.

     

Prevalence and Causes of Prescribing Errors: The PRescribing Outcomes for Trainee Doctors Engaged in Clinical Training (PROTECT) Study

Objectives

Study objectives were to investigate the prevalence and causes of prescribing errors amongst foundation doctors (i.e. junior doctors in their first (F1) or second (F2) year of post-graduate training), describe their knowledge and experience of prescribing errors, and explore their self-efficacy (i.e. confidence) in prescribing.

Method

A three-part mixed-methods design was used, comprising: prospective observational study; semi-structured interviews and cross-sectional survey. All doctors prescribing in eight purposively selected hospitals in Scotland participated. All foundation doctors throughout Scotland participated in the survey. The number of prescribing errors per patient, doctor, ward and hospital, perceived causes of errors and a measure of doctors'' self-efficacy were established.

Results

4710 patient charts and 44,726 prescribed medicines were reviewed. There were 3364 errors, affecting 1700 (36.1%) charts (overall error rate: 7.5%; F1:7.4%; F2:8.6%; consultants:6.3%). Higher error rates were associated with : teaching hospitals (p<0.001), surgical (p = <0.001) or mixed wards (0.008) rather thanmedical ward, higher patient turnover wards (p<0.001), a greater number of prescribed medicines (p<0.001) and the months December and June (p<0.001). One hundred errors were discussed in 40 interviews. Error causation was multi-factorial; work environment and team factors were particularly noted. Of 548 completed questionnaires (national response rate of 35.4%), 508 (92.7% of respondents) reported errors, most of which (328 (64.6%) did not reach the patient. Pressure from other staff, workload and interruptions were cited as the main causes of errors. Foundation year 2 doctors reported greater confidence than year 1 doctors in deciding the most appropriate medication regimen.

Conclusions

Prescribing errors are frequent and of complex causation. Foundation doctors made more errors than other doctors, but undertook the majority of prescribing, making them a key target for intervention. Contributing causes included work environment, team, task, individual and patient factors. Further work is needed to develop and assess interventions that address these.     

What helps and hinders midwives in engaging with pregnant women about stopping smoking? A cross-sectional survey of perceived implementation difficulties among midwives in the North East of England

ABSTRACT: BACKGROUND: Around 5,000 miscarriages and 300 perinatal deaths per year result from maternal smoking in the United Kingdom. In the northeast of England, 22% of women smoke at delivery compared to 14% nationally. Midwives have designated responsibilities to help pregnant women stop smoking. We aimed to assess perceived implementation difficulties regarding midwives' roles in smoking cessation in pregnancy. METHODS: A self-completed, anonymous survey was sent to all midwives in northeast England (n?=?1,358) that explores the theoretical explanations for implementation difficulties of four behaviours recommended in the National Institute for Health and Clinical Excellence (NICE) guidance: (a) asking a pregnant woman about her smoking behaviour, (b) referring to the stop-smoking service, (c) giving advice about smoking behaviour, and (d) using a carbon monoxide monitor. Questions covering Michie et al.'s theoretical domain framework (TDF), describing 11 domains of hypothesised behavioural determinants (i.e., 'knowledge', 'skills', 'social/professional role/identity', 'beliefs about capabilities', 'beliefs about consequences', 'motivation and goals', 'memory', 'attention and decision processes', 'environmental context and resources', 'social influences', 'emotion', and 'self-regulation/action planning'), were used to describe perceived implementation difficulties, predict self-reported implementation behaviours, and explore relationships with demographic and professional variables. RESULTS: The overall response rate was 43% (n?=?589). The number of questionnaires analysed was 364, following removal of the delivery-unit midwives, who are not directly involved in providing smoking-cessation services. Participants reported few implementation difficulties, high levels of motivation for all four behaviours and identified smoking-cessation work with their role. Midwives were less certain about the consequences of, and the environmental context and resources available for, engaging in this work relative to other TDF domains. All domains were highly correlated. A principal component analysis showed that a single factor ('propensity to act'), derived from all domains, explained 66% of variance in theoretical domain measures. The 'propensity to act' was predictive of the self-reported behaviour 'Refer all women who smoke……to NHS Stop Smoking Services' and mediated the relationship between demographic variables, such as midwives' main place of work, and behaviour. CONCLUSIONS: Our findings advance understanding of what facilitates and inhibits midwives' guideline implementation behaviours in relation to smoking cessation and will inform the development of current practice and new interventions. Using the TDF as a self-completion questionnaire is innovative, and this study supports previous research that the TDF is an appropriate tool to understand the behaviour of healthcare professionals.     

Antibiotic Prescribing in DR Congo: A Knowledge,Attitude and Practice Survey among Medical Doctors and Students

Objectives

Antibiotic resistance (ABR) particularly hits resource poor countries, and is fuelled by irrational antibiotic (AB) prescribing. We surveyed knowledge, attitudes and practices of AB prescribing among medical students and doctors in Kisangani, DR Congo.

Methods

Self-administered questionnaires.

Results

A total of 184 questionnaires were completed (response rate 94.4%). Knowledge about AB was low (mean score 4.9/8 points), as was the estimation of local resistance rates of S. Typhi and Klebsiella spp.(correct by 42.5% and 6.9% of respondents respectively). ABR was recognized as a problem though less in their own practice (67.4%) than nation- or worldwide (92.9% and 85.5%, p<.0001). Confidence in AB prescribing was high (88.6%) and students consulted more frequently colleagues than medical doctors when prescribing (25.4% versus 11.6%, p  = 0.19). Sources of AB prescribing included pharmaceutical companies (73.9%), antibiotic guidelines (66.3%), university courses (63.6%), internet-sites (45.7%) and WHO guidelines (26.6%). Only 30.4% and 16.3% respondents perceived AB procured through the central procurement and local pharmacies as of good quality. Local AB guidelines and courses about AB prescribing are welcomed (73.4% and 98.8% respectively).

Conclusions

This data shows the need for interventions that support rational AB prescribing.     

Unpacking collaborative depression care: examining two essential tasks for implementation

Clinical guidelines recommend that assessment and management of patients with stroke commences early including in emergency departments (ED). To inform the development of an implementation intervention targeted in ED, we conducted a systematic review of qualitative and quantitative studies to identify relevant barriers and enablers to six key clinical behaviours in acute stroke care: appropriate triage, thrombolysis administration, monitoring and management of temperature, blood glucose levels, and of swallowing difficulties and transfer of stroke patients in ED. Studies of any design, conducted in ED, where barriers or enablers based on primary data were identified for one or more of these six clinical behaviours. Major biomedical databases (CINAHL, OVID SP EMBASE, OVID SP MEDLINE) were searched using comprehensive search strategies. The barriers and enablers were categorised using the theoretical domains framework (TDF). The behaviour change technique (BCT) that best aligned to the strategy each enabler represented was selected for each of the reported enablers using a standard taxonomy. Five qualitative studies and four surveys out of the 44 studies identified met the selection criteria. The majority of barriers reported corresponded with the TDF domains of “environmental, context and resources” (such as stressful working conditions or lack of resources) and “knowledge” (such as lack of guideline awareness or familiarity). The majority of enablers corresponded with the domains of “knowledge” (such as education for physicians on the calculated risk of haemorrhage following intravenous thrombolysis [tPA]) and “skills” (such as providing opportunity to treat stroke cases of varying complexity). The total number of BCTs assigned was 18. The BCTs most frequently assigned to the reported enablers were “focus on past success” and “information about health consequences.” Barriers and enablers for the delivery of key evidence-based protocols in an emergency setting have been identified and interpreted within a relevant theoretical framework. This new knowledge has since been used to select specific BCTs to implement evidence-based care in an ED setting. It is recommended that findings from similar future reviews adopt a similar theoretical approach. In particular, the use of existing matrices to assist the selection of relevant BCTs.     

Doctors,physiotherapists, and placebo pharmacology.

A seminar of physiotherapists studied the psychological aspects of their work. Difficulty with doctors rather than patients was unexpectedly prominent. The following factors were identified as contributing to their dissatisfaction: doctors misused physiotherapy as a placebo in cases of incurable and untreatable disease and mental problems; because they faced questions about diagnosis and prognosis that doctors escaped they learnt to avoid knowing the facts about their patients; using quasiscientific apparatus had tended to replace physical contact; they saw their psychological skill as illicit and unprofessional; and they were uncertain about their role as social workers. Nevertheless, they tended to idealise doctors, which sharpened gratification in collaborative work and helped to alleviate anxiety about death and disease, but tended to reinforce sexual stereotyping and the image of physiotherapy as "unscientific," empirical, and intuititive ("feminine").     

Witness response at acute onset of stroke: a qualitative theory-guided study

Background

Delay in calling emergency medical services following stroke limits access to early treatment that can reduce disability. Emergency medical services contact is mostly initiated by stroke witnesses (often relatives), rather than stroke patients. This study explored appraisal and behavioural factors that are potentially important in influencing witness behaviour in response to stroke.

Methods and Findings

Semi-structured interviews with 26 stroke witnesses were transcribed and theory-guided content analysed was undertaken based on the Common Sense Self-Regulation Model (appraisal processes) and Theory Domains Framework (behavioural determinants). Response behaviours were often influenced by heuristics-guided appraisal (i.e. mental rules of thumb). Some witnesses described their responses to the situation as ‘automatic’ and ‘instinctive’, rather than products of deliberation. Potential behavioural influences included: environmental context and resources (e.g. time of day), social influence (e.g. prompts from patients) and beliefs about consequences (e.g. 999 accesses rapid help). Findings are based on retrospective accounts and need further verification in prospective studies.

Conclusions

Witnesses play a key role in patient access to emergency medical services. Factors that potentially influence witnesses’ responses to stroke were identified and could inform behavioural interventions and future research. Interventions might benefit from linking automatic/instinctive threat perceptions with deliberate appraisal of stroke symptoms, prompting action to call emergency medical services.     

Uncomfortable prescribing decisions: a critical incident study.

OBJECTIVE--To explore the discomfort experienced by general practitioners in relation to decisions about whether or not to prescribe. DESIGN--Focused interviews of general practitioners about prescribing decisions that made them uncomfortable. Analysis based on the critical incident technique. SETTING--One family practitioner committee area in the north of England. RESPONDENTS--69 principals and five trainee general practitioners. MAIN OUTCOME MEASURES--Drugs and clinical problems associated with prescribing discomfort. Reasons given by doctors for making the prescribing decisions they did and reasons for feeling uncomfortable. RESULTS--Antibiotics, tranquillisers, hypnotics, and symptomatic remedies were most often associated with discomfort, but any prescribable item could be associated with discomfort. Respiratory diseases, musculoskeletal problems, and anxiety were most often associated with discomfort, but again any condition could be associated. The main reasons given for the decisions made were patient expectation, clinical appropriateness, factors related to the doctor-patient relationship, and precedents. The main reasons given for feeling uncomfortable were concern about drug toxicity, failure to live up to the general practitioner''s own expectations, concern about the appropriateness of treatment, and ignorance or uncertainty. CONCLUSIONS--Many considerations, including medical, social, and logistic ones, influence the decision to prescribe in general practice. The final action taken depends on a complex interaction of these disparate influences.     

What Are Lay Theories of Social Class?

Numerous studies have documented the effects of social class on psychological and behavioral variables. However, lay beliefs about how social class affects these dimensions have not been systematically tested. Studies 1 and 2 assessed lay beliefs about the association between social class and 8 variables (including psychological and behavioral tendencies and cognitive ability). Study 3 assessed lay beliefs about the Big five personality traits and social class, and study 4 reframed the 8 variables from study 1 in opposite terms and yielded similar results. Study 5 contained the variables framed as in both studies 1 and 4, and replicated those results suggesting that framing effects were not responsible for the effects observed. Interestingly, for the most part lay beliefs about social class did not differ as a function of participants’ own social class. In general people held relatively accurate and consistent stereotypes about the relationship between social class and well-being, health, intelligence, and neuroticism. In contrast lay beliefs regarding social class and reasoning styles, as well as relational, social, and emotional tendencies were less consistent and coherent. This work suggests that on the whole people’s beliefs about social class are not particularly accurate, and further that in some domains there are contradictory stereotypes about the consequences of social class.     

Evaluation of a web-based intervention to reduce antibiotic prescribing for LRTI in six European countries: quantitative process analysis of the GRACE/INTRO randomised controlled trial

Background

To reduce the spread of antibiotic resistance, there is a pressing need for worldwide implementation of effective interventions to promote more prudent prescribing of antibiotics for acute LRTI. This study is a process analysis of the GRACE/INTRO trial of a multifactorial intervention that reduced antibiotic prescribing for acute LRTI in six European countries. The aim was to understand how the interventions were implemented and to examine effects of the interventions on general practitioners’ (GPs’) and patients’ attitudes.

Methods

GPs were cluster randomised to one of three intervention groups or a control group. The intervention groups received web-based training in either use of the C-reactive protein (CRP) test, communication skills and use of a patient booklet, or training in both. GP attitudes were measured before and after the intervention using constructs from the Theory of Planned Behaviour and a Website Satisfaction Questionnaire. Effects of the interventions on patients were assessed by a post-intervention questionnaire assessing patient enablement, satisfaction with the consultation, and beliefs about the risks and need for antibiotics.

Results

GPs in all countries and intervention groups had very positive perceptions of the intervention and the web-based training, and felt that taking part had helped them to reduce prescribing. All GPs perceived reducing prescribing as more important and less risky following the intervention, and GPs in the communication groups reported increased confidence to reduce prescribing. Patients in the communication groups who received the booklet reported the highest levels of enablement and satisfaction and had greater awareness that antibiotics could be unnecessary and harmful.

Conclusions

Our findings suggest that the interventions should be broadly acceptable to both GPs and patients, as well as feasible to roll out more widely across Europe. There are also some indications that they could help to engender changes in GP and patient attitudes that will be helpful in the longer-term, such as increased awareness of the potential disadvantages of antibiotics and increased confidence to manage LRTI without them. Given the positive effects of the booklet on patient beliefs and attitudes, it seems logical to extend the use of the patient booklet to all patients.

     

Identifying patterns of eating and physical activity in children: a latent class analysis of obesity risk

We used latent class analysis (LCA) to identify heterogeneous subgroups with respect to behavioral obesity risk factors in a sample of 4th grade children (n = 997) residing in Southern California. Multiple dimensions assessing physical activity, eating and sedentary behavior, and weight perceptions were explored. A set of 11 latent class indicators were used in the analysis. The final model yielded a five-class solution: "High-sedentary, high-fat/high-sugar (HF/HS) snacks, not weight conscious," "dieting without exercise, weight conscious," "high-sedentary, HF/HS snacks, weight conscious," "active, healthy eating," and "low healthy, snack food, inactive, not weight conscious." The results suggested distinct subtypes of children with respect to obesity-related risk behaviors. Ethnicity, gender, and a socioeconomic status proxy variable significantly predicted the above latent classes. Overweight or obese weight status was determined based on the Centers for Disease Control and Prevention BMI (kg/m2)-for-age-and-sex percentile (overweight, 85th percentile ≤ BMI < 95th percentile; obese, 95th percentile ≤ BMI). The identified latent subgroup membership, in turn, was associated with the children's weight categories. The results suggest that intervention programs could be refined or targeted based on children's characteristics to promote effective pediatric obesity interventions.     

Culture and Rights after Culture and Rights

Building on a critical, theoretical approach outlined in Culture and Rights: Anthropological Perspectives (Cowan et al. 2001a), I posit rights processes as complex and contradictory: Both enabling and constraining, they produce new subjectivities and social relations and entail unintended consequences. To encourage interdisciplinary engagement on these themes, I explore selected texts that consider the relationship between culture and rights, addressing two literatures: (1) debates on culture, rights, and recognition in the context of multiculturalism among political philosophers and (2) an emerging literature by anthropologists, feminists, critical legal scholars, and engaged practitioners analyzing empirical cases. Although political philosophers elucidate ethical implications and clarify political projects, an outmoded arsenal of theoretical concepts of "culture,""society," and "the individual" has hampered their debates. When accounts are both theoretically informed and empirically grounded, contradictions, ambiguities, and impasses of culture and rights are more fully explored and the liberal model of rights and multiculturalism is more open to interrogation.     

Effectiveness of Cultural Adaptations of Interventions Aimed at Smoking Cessation,Diet, and/or Physical Activity in Ethnic Minorities. A Systematic Review

Background

The importance of cultural adaptations in behavioral interventions targeting ethnic minorities in high-income societies is widely recognized. Little is known, however, about the effectiveness of specific cultural adaptations in such interventions.

Aim

To systematically review the effectiveness of specific cultural adaptations in interventions that target smoking cessation, diet, and/or physical activity and to explore features of such adaptations that may account for their effectiveness.

Methods

Systematic review using MEDLINE, PsycINFO, Embase, and the Cochrane Central Register of Controlled Trials registers (1997–2009). Inclusion criteria: a) effectiveness study of a lifestyle intervention targeted to ethnic minority populations living in a high income society; b) interventions included cultural adaptations and a control group that was exposed to the intervention without the cultural adaptation under study; c) primary outcome measures included smoking cessation, diet, or physical activity.

Results

Out of 44904 hits, we identified 17 studies, all conducted in the United States. In five studies, specific cultural adaptations had a statistically significant effect on primary outcomes. The remaining studies showed no significant effects on primary outcomes, but some presented trends favorable for cultural adaptations. We observed that interventions incorporating a package of cultural adaptations, cultural adaptations that implied higher intensity and those incorporating family values were more likely to report statistically significant effects. Adaptations in smoking cessation interventions seem to be more effective than adaptations in interventions aimed at diet and physical activity.

Conclusion

This review indicates that culturally targeted behavioral interventions may be more effective if cultural adaptations are implemented as a package of adaptations, the adaptation includes family level, and where the adaptation results in a higher intensity of the intervention. More systematic experiments are needed in which the aim is to gain insight in the best mix of cultural adaptations among diverse populations in various settings, particularly outside the US.     

Mutual inhibitory activities of tumor-degenerating factor (TDF) and fibronectin

It was reported in our previous studies that the "spongy degeneration-like" changes of human tumor cells were detected by coculture with human embryonic fibroblasts in vitro. It was discovered that the degenerative changes were mediated by a factor secreted from human embryonic fibroblasts. This factor was named the tumor-degenerating factor (TDF). The present study found that fibronectin inhibited TDF activity while TDF inhibited cell attachment mediated by fibronectin. It was possible that these mutual inhibitions were due to the direct binding of the TDF molecule to the fibronectin molecule. Since it is well known that fibronectin is composed of multiple domains which differ in their biological activities, this study also attempted to clarify which domain(s) inhibit TDF activity, through the use of trypsin, thermolysin and 2-nitro-5-thiocyanobenzoic acid (NTCB). It is concluded that multiple domains of fibronectin are required for the inhibition of TDF activity.     

Effectiveness of instruction in critical appraisal (evidence-based medicine) skills: a critical appraisal

OBJECTIVE: To examine the evidence that the teaching of critical appraisal (evidence-based medicine) skills to undergraduate medical students or residents will result in significant gains in knowledge and increased use of the literature in clinical decision-making. DATA SOURCES: Articles published from 1966 to 1995, retrieved through a MEDLINE search supplemented by manual searches; review of bibliographies maintained by individuals involved in teaching critical appraisal skills; and a previous methodological review. STUDY SELECTION: Articles were selected if the study involved some form of control group, although strict randomization was not required, and a measure of performance followed the intervention. Articles were excluded if they simply reported the process of teaching critical appraisal skills or used some form of "happiness index." DATA SYNTHESIS: There were 10 studies of the impact of teaching critical appraisal skills, 6 involving medical students and 4 involving residents. Results from 3 of the studies were nearly uninterpretable and thus were excluded; the remaining 7 were methodologically acceptable. Analysis showed that interventions implemented in undergraduate programs resulted in significant gains in knowledge, as assessed by a written test (mean gain 17.0%; standard deviation [SD] 4.0%). Conversely, studies at the residency level consistently showed a small change in knowledge (mean gain 1.3%; SD 1.7%). Two studies that examined residents'' use of the literature were unable to demonstrate any positive changes. CONCLUSIONS: Studies of the effect of teaching critical appraisal skills on gains in knowledge at the undergraduate level showed consistent improvement. By contrast, changes in knowledge at the residency level were small. Several suggestions from the educational literature are offered to increase effectiveness of critical appraisal interventions.