Rheumatoid arthritis: the importance of evidence based diagnostic reasoning in preventing debilitating consequences.

BACKGROUND: The early diagnosis of Rheumatoid arthritis can improve clinical outcomes, in terms of morbidity and mortality. This study evaluates the role of evidence informed diagnostic reasoning in the early diagnosis of Rheumatoid arthritis. METHODS: A cross-sectional survey was conducted on 200 respondents inclusive of doctors and medical students, at Shifa college of Medicine, Islamabad from April to December 2010. A questionnaire with three common clinical scenarios of low, intermediate and high pre-test probability for rheumatoid arthritis (RA) was provided to the respondents. The differences between the reference and respondents' estimates of pre and post-test probability were used to assess the respondents' clinical diagnostic reasoning process, as a tool to diagnose RA early. Respondents were also enquired about the cost effectiveness or potential harms of Rheumatoid factor (RF). Consecutive sampling technique was used and the data was analysed using SPSS-15. RESULTS: In all scenarios, the pre-test probability was estimated close to the reference estimates suggesting respondents' ability to rule in or rule out the disease. However, some over-estimation of the pre-test probability was noticed in low and intermediate pre-test probability settings. Post-test probabilities were significantly underestimated reflecting their inability to calculate post-test probabilities in all scenarios. More tests were ordered as the disease probability increased. Most respondents were of the opinion that RF is cost effective and safe. CONCLUSIONS: The significant underestimation of the post-test probability necessitates more emphasis on Bayesian probabilistic thinking in clinical practice to facilitate early diagnosis of rheumatoid arthritis.

Impact of probability estimation on frequency of urine culture requests in ambulatory settings.

OBJECTIVE: To determine the perceptions of the medical community about urine culture in diagnosing urinary tract infections. METHODS: The cross-sectional survey based of consecutive sampling was conducted at Shifa International Hospital, Islamabad, on 200 doctors, including medical students of the Shifa College of Medicine, from April to October 2010. A questionnaire with three common clinical scenarios of low, intermediate and high pre-test probability for urinary tract infection was used to assess the behaviour of the respondents to make a decision for urine culture test. The differences between the reference estimates and the respondents' estimates of pre- and post-test probability were assessed. The association of estimated probabilities with the number of tests ordered was also evaluated. The respondents were also asked about the cost effectiveness and safety of urine culture and sensitivity. Data was analysed using SPSS version 15. RESULTS: In low pre-test probability settings, the disease probability was over-estimated, suggesting the participants' inability to rule out the disease. The post-test probabilities were, however, under-estimated by the doctors as compared to the students. In intermediate and high pre-test probability settings, both over- and underestimation of probabilities were noticed. Doctors were more likely to consider ordering the test as the disease probability increased. Most of the respondents were of the opinion that urine culture was a cost-effective test and there was no associated potential harm. CONCLUSIONS: The wide variation in the clinical use of urine culture necessitates the formulation of appropriate guidelines for the diagnostic use of urine culture, and application of Bayesian probabilistic thinking to real clinical situations.

The clinical diagnostic reasoning process determining the use of endoscopy in diagnosing peptic ulcer disease.

OBJECTIVE: To evaluate the clinical diagnostic reasoning process as a tool to decrease the number of unnecessary endoscopies for diagnosing peptic ulcer disease. tudy DESIGN: Cross-sectional KAP study. PLACE AND DURATION OF STUDY: Shifa College of Medicine, Islamabad, from April to August 2010. METHODOLOGY: Two hundred doctors were assessed with three common clinical scenarios of low, intermediate and high pre-test probability for peptic ulcer disease using a questionnaire. The differences between the reference estimates and the respondents' estimates of pre-test and post test probability were used for assessing the ability of estimating the pretest probability and the post test probability of the disease. Doctors were also enquired about the cost-effectiveness and safety of endoscopy. Consecutive sampling technique was used and the data was analyzed using SPSS version 16. RESULTS: In the low pre-test probability settings, overestimation of the disease probability suggested the doctors' inability to rule out the disease. The post test probabilities were similarly overestimated. In intermediate pre-test probability settings, both over and under estimation of probabilities were noticed. In high pre-test probability setting, there was no significant difference in the reference and the responders' intuitive estimates of post test probability. Doctors were more likely to consider ordering the test as the disease probability increased. Most respondents were of the opinion that endoscopy is not a cost-effective procedure and may be associated with a potential harm. CONCLUSION: Improvement is needed in doctors' diagnostic ability by more emphasis on clinical decision-making and application of bayesian probabilistic thinking to real clinical situations.

Making evidence-based medicine (EBM) doable in developing countries: a locally-tailored workshop for EBM in a Pakistani institution.

OBJECTIVE: To demonstrate that evidence-based medicine (EBM) training can be imparted in developing countries using minimal resources. DESIGN: Development of a minimal cost workshop with validation of gain in EBM skills using the Berlin questionnaire. SETTING: Teaching hospital in Pakistan. PARTICIPANTS: Multidisciplinary faculty from The Shifa College of Medicine and Nursing, Pakistan. INTERVENTION: A 14-hour locally-tailored McMaster-style workshop, using a problem-based, learner-focused small group format, with pre- and post-workshop evaluation of EBM skills. RESULTS: Analysis of the pre- and post-Berlin questionnaires of the participants revealed that the pre-workshop Berlin questionnaire score for the group was 4.7+/-2.3, with a post-workshop Berlin score of 7.6+/-1.0 (p<0.001). CONCLUSION: EBM workshops can be locally-tailored in developing countries, where access to such workshops is generally not available. Workshops can serve to promote EBM skills in faculty, who can then help to disseminate and model concepts. The process increases awareness and interest in EBM, which in this case resulted in formation of a national platform for EBM.