Study	Reason for exclusion
Alarcón 1994	The study was provisionally excluded pending clarification of the nature of the intervention, which did not clearly seem to consist of teaching critical appraisal. Further, it was not clear what the control group had received. Unfortunately, no clarification was received and the study was effectively excluded, despite clearly being of potential relevance.
Bennett 1987	This controlled trial of 92 medical students compared 8 seminars on critical appraisal with control group measuring skills. This was excluded as it did not teach qualified healthcare workers.
Burls 1997	This was a multidisciplinary 1‐day workshop teaching critical appraisal to 1880 healthcare workers, and evaluating self assessed knowledge and attitudes. The study was excluded as it did not assess outcomes using objective measures.
Burstein 1996	This before and after study in emergency medicine residents assessed the impact of a structured review instrument in a journal club on overall satisfaction, perceived educational value, attendance and workload. It was excluded as the instrument did not constitute teaching of critical appraisal.
Caudill 1993	This before and after study evaluated a comprehensive multi component course in critical appraisal skills for medical residents. Knowledge, attitudes and behaviour were the outcomes assessed after the 6‐month course, with knowledge outcomes being assessed by objective validated measures (same as in Linzer RCT). This study was excluded as it did not have a control comparison group and did not meet other inclusion criteria for study methodology.
Cuddy 1984	This controlled trial of 18 medical students involved the evaluation of slide tape presentation/lecture teaching critical appraisal. It was excluded as it did not teach qualified healthcare workers, and had not stated the validity of instruments used.
Domholdt 1994	This study compared the critical appraisal skills of inexperienced and expert physical therapists and examined factors influencing critical appraisal skills. It was excluded as the impact of teaching of critical appraisal was not evaluated.
Dorsch 1990	Description of the development of a critical appraisal teaching intervention for the study by Frasca. It was excluded because it was duplicative.
Fowkes 1984	This before and after study evaluated an epidemiology course for medical students which included teaching critical appraisal. It was excluded on confirmation that there was no separable data for that part of the course teaching critical appraisal.
Frasca 1992	This was a controlled trial of 92 medical students comparing 10 seminars on critical appraisal teaching and assessing skills. This was excluded as it did not teach qualified healthcare workers.
Gehlbach 1980	This controlled trial of 35 US family medicine residents evaluated 8 seminars of critical appraisal teaching with examination at end of year. It was excluded as validation of instrument was not stated.
Gehlbach 1985	This controlled trial compared teaching an 'Epidemiology for Clinical Practice' course delivered by lectures, small group seminars or self learning packages. It was excluded because there was no comparison with critical appraisal teaching. It was identified as a potentially useful study outside the immediate context of this review.
Globerman 1993	This describes the development of a course to teach critical appraisal skills to social workers. The main focus is descriptive, but there is reference to evaluation. It was excluded because there was no comparison group and no pre‐course assessment.
Griffith 1988	This study reported a course that focused on teaching critical appraisal skills to medical students. It was excluded because there was no comparison group and no pre‐course assessment.
Harewood 2009	This study was a 1 group pre‐post study
Heiligman 1991	This study identified attitudes of family practice residents toward a journal club and the identification of factors contributing to the success of the journal club. It was excluded because there was no comparison group and no pre‐course assessment.
Heller 1984	This controlled trial assessed the impact of a general epidemiology and public health course to medical students. Although the course included the development of a critical approach to information, it was excluded because it was judged to be a small component, the effect of which could not be separated.
Herbert 1990	This study reported a course teaching critical appraisal to residents and its application in an innovative debate format for making clinical decisions. It was excluded because no comparative evaluative data were presented, the absence of which was confirmed by the author.
Hicks 1994	This was a within‐group study of 19 midwives in the UK following a 1‐day workshop on critical appraisal teaching. The outcomes measured were skills and self assessed behaviour changes. This study was excluded because it did not assess outcomes specified in the inclusion criteria and did not use objective measures of those outcomes that fulfilled our relevance criteria.
Hillson 1993	This was a within‐group comparison of 29 residents who had 7 hours of lectures and journal clubs. Critical appraisal skills were assessed. This study was excluded as it did not assess outcomes specified in the inclusion criteria.
Ibbotson 1998	This was a multidisciplinary 1‐day workshop teaching critical appraisal to 115 healthcare workers, and evaluating self assessed knowledge and attitudes. This study was excluded as it did not assess outcomes using objective measures.
Inui 1981	This described a seminar series for teaching critical appraisal skills to second year residents. It was excluded because no comparative data were presented.
Johnson 1995	See Reineck 1995
Kerrison 1995	This study assessed the impact of a series of 23 workshops involving an estimated 130 participants, including managers, clinicians and researchers. The main focus of the evaluation was qualitative; some quantitative data were collected. It was excluded because no comparative data were presented. Confirmation of this from the lead author was sought but not obtained.
Kitchens 1989	This was a within‐group comparison and between‐group cross‐over trial of 83 internal medicine interns involving critical appraisal seminars and assessing knowledge. This was excluded because it had not stated the validity of instruments used.
Konen 1990	This described 5 years of experience with a curriculum teaching critical appraisal skills to family practice residents. It was excluded because no comparison group data were available, a fact confirmed by the author.
Krueger 2006	This was excluded because the intervention occurred with medical students and not qualified health workers
Landry 1994	This was a controlled trial of 146 medical students with 3 hours of large‐group seminars teaching critical appraisal. Outcomes assessed were knowledge and attitudes. This was excluded as it did not teach qualified healthcare workers.
Langkamp 1992	This controlled before and after study assessed the impact of 2 didactic sessions on research design, clinical epidemiology and biostatistics followed by 8 monthly journal club sessions to 27 paediatric residents at 2 institutions. It was provisionally included pending confirmation that the intervention was critical appraisal teaching, and that it was being compared to no teaching. Unfortunately, no clarification was received and the study was effectively excluded, despite clearly being of potential relevance.
Linzer 1987a	This quasi‐randomised controlled trial compared a journal club for residents teaching clinical epidemiology and biostatistical skills co‐ordinated by a general medicine faculty member with a special interest and training in clinical epidemiology, biostatistics and critical appraisal, versus one co‐ordinated by a chief resident. It was excluded because it did not assess the impact of teaching critical appraisal, but rather 2 alternative approaches to teaching of critical appraisal. It was identified as a potentially useful study outside the immediate context of this review.
MacAuley 1996	This study was excluded because it evaluated an instrument to aid critical appraisal and not the impact of teaching it
MacAuley 1997	This study was excluded because it evaluated an instrument to aid critical appraisal and not the impact of teaching it
MacAuley 1998	This study was excluded because it evaluated an instrument to aid critical appraisal and not the impact of teaching it
MacAuley 1999	This study was excluded because it evaluated an instrument to aid critical appraisal and not the impact of teaching it
Markert 1989	This described the development of a journal club teaching medical residents how to read and critically appraise the medical literature. It was excluded because there was no comparison group and no pre‐course assessment.
Milne 1996	This study evaluated critical appraisal workshops designed to develop skills needed to make sense of evidence about effectiveness for people who give health information to the public, especially staff in consumer health information services and members of maternity self help groups. It was excluded because there was no comparison group and no pre‐course assessment.
Mulvihill 1973	This study described a course in epidemiology and biostatistics to medical students. It was excluded because teaching critical appraisal did not appear to be a major component of the course. Further, there were only minimal data on evaluation.
Mulvihill 1980	See above reference by same author
Novick 1985	The second part of the epidemiology course described was concerned with the teaching of critical appraisal skills. It was excluded because there was no comparison group and no pre‐course assessment.
O'Sullivan 1995	This study assessed general internal medicine residents' perception of how 2 methods of teaching critical appraisal affected their reading habits, presentation skills and critical appraisal skills. It was excluded as no comparison with no critical appraisal teaching was provided. It was identified as a potentially useful study outside the immediate context of this review.
Radack 1986	This controlled trial of 34 medical students compared 5 problem‐based critical appraisal sessions with a control group. Outcomes assessed were critical appraisal skills. This was excluded as it did not teach qualified healthcare workers, and did not state the validity of instruments used.
Reineck 1995	This publication described a pilot study of a critical reading of research programme over 6 sessions for nurses following on from the preliminary work by Jean Johnson. It was excluded because there was no comparison group and no pre‐course assessment, although it was indicated that the latter had been collected in the associated paper by Johnson.
Riegelman 1986	This controlled trial of 296 medical students compared critical appraisal seminars and a lecture course with control group. It was excluded as it did not teach qualified healthcare workers, and had not stated the validity of instruments used.
Romm 1989	This randomised controlled trial compared teaching critical appraisal using either small group formats or lectures. It was excluded because it had no comparison group not being taught critical appraisal. It was identified as a potentially useful study outside the immediate context of this review.
Salmi 1991	This French paper was a tutorial on the critical appraisal process and was excluded because it was not an evaluation
Sandifer 1996	This study was set in a department of public health in South Glamorgan Health Authority, UK and assessed the use of a journal club as a learning environment to practise critical appraisal skills. The proxy outcome indicators used were impact on commissioning policy and publication of letters to the editor of the journal from which the appraisers' articles were selected. It was excluded because there was no comparison group and no pre‐course assessment.
Seelig 1991	This was a within‐group comparison of 18 internal medicine internists following a 1‐hour teaching session on critical appraisal and assessing knowledge, skills and attitudes. Ultimately this publication was excluded because it did not use a validated instrument.
Seelig 1993	This publication examined a within‐group comparison of 14 internal medicine residents who had one lecture and 8 journal club sessions on critical appraisal skills. Skills, knowledge and attitudes were assessed. This was excluded as it did not state the validity of instruments used.
Stern 1995	This study was excluded as it was developing and validating an instrument to evaluate the abilities of residents to critically appraise a journal article and not the teaching of critical appraisal skills.
Viniegra 1994	By the same authors as the excluded study Alarcon 1994, this Mexican study involved the evaluation of critical appraisal skills in medical students and an attempt to relate differences observed to other characteristics, such as years of medical training. It was excluded as it did not involve teaching critical appraisal.

RCT: randomised controlled trial