Cabell 2001.

Methods	Study design: RCT Data collection: automated tracking of database logins Unit of analysis issues: none noted
Participants	Participants: 48 medical residents Total number randomized: 48; 24 in each group Practitioners lost to follow‐up: 1 Baseline characteristics of participants: Age, median (IQR): IG: 29.0 years (2.9); CG 29.3 years (3.2) Gender: IG: 24; 8 women; CG: 24; 8 women Setting: general internal medicine service, Duke University Medical Center Country: USA
Interventions	Description: 1‐hour didactic session taught by principle investigator (Cabell) and a medical librarian: introduction to EBM process; discussion of WBCQ based on PICO framework; introduction to WBCQ cards; practice formulating questions; overview of MEDLINE searching; practice searching MEDLINE (p. 839, Figure 1; p. 839, last para, col 1) Using WBCQ cards to "record clinical questions generated from each admission" (p. 839, col 2, para 1; p. 40, Figure 2) "Use of WBCQ cards to build searchable questions generated from admissions to the general medicine service. The cards were used each long call night [and were presented to] the chief resident [during one on one sessions]. During these sessions...residents presented [his/her] admissions [and] clinical questions derived from [them]. [Then the chief resident emphasized] the relationship between the development of a clinical questions, the use of the WBCQ cards, and...expedient searching of the medical literature" (p. 839, col 2, para 2). "Residents kept the [WBCQ] cards and used them to aid in formulating their search strategies in MEDLINE...the residents were encouraged to...search each...question, and to bring the data back to their teams to aid in patient care" (p. 839, col 2, para 3). The IG also received the usual education Type of intervention: Multifaceted education: didactic session with interactive aspects ‐ MEDLINEsearching and practice formulating clinical questions Provision of educational material: residents were provided with WBCQ cards to use during on call night shifts Study period: September 1998 to May 1999 Intervention delivery periods: 6 inpatient medical rotations, each lasting 6‐8 weeks(p. 838, col 2, para 4) Duration of intervention: 1‐hour didactic session (during week 1 of rotation) (p. 839, col 1, para 6). 12‐14 meetings with chief resident during long‐call nights(p. 839, col 1, para 1) Data collection time: not clearly stated "The data collected from the first week of each rotation were not used for analysis to reduce contamination between groups at the time of rotation changes" (p. 843, col 2, para 4) Comparison: CG received "usual" educational sessions with a medical librarian and also met with the chief resident: "the chief resident sessions were similar for each group except for the time spent on practical experience formulating well‐built clinical questions and the use of the WBCQ cards" (p. 840, col 1, para 1) Notes: Chief resident training: Chief residents were trained in EBM (p. 839, col 1, para 2). "The chief residents receive specific training in EBM both through our training program and through workshop attendance. The chief residents attend the McMaster University workshop on the principles of teaching EBM. This workshop combines didactic lessons with small group discussion sections. In addition, practice teaching sessions with role playing are used to facilitate the development of practical skills in teaching EBM to learners such as medical residents" Usual education: The IG also received "usual" education with a medical librarian (p. 839, col 1, para 4). Usual education consisted of: "The medical librarian sessions were 30‐minute lessons on the different resources available to locate important medical information. These sessions took place just before morning report 1 day per week. These sessions followed a structured curriculum that included the use of medical subject headings and subheadings, text words, EBM filters, and other EHI such as Best Evidence and the Cochrane Database of Systematic Reviews. Each week the medical librarian provided pragmatic examples of how the answers to medical questions could be answered utilizing specific techniques and electronic medical resources [e.g. EHI]"
Outcomes	Number of times each resident accessed Ovid MEDLINE during his/her general medicine rotation
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"[48] residents...were randomly assigned in blocks by coin flip to a teaching intervention or to a control group" (p. 838, col 2, para 4)
Allocation concealment (selection bias)	Low risk	Adequate due to block randomization(p. 838)
Blinding (performance bias and detection bias) All outcomes	Low risk	Performance bias: low "Although study participants were blinded to the study question, it is impossible to know if contamination between groups was totally prevented. The data collected from the first week of each rotation were not used for analysis to reduce contamination between groups at the time of rotation changes" (p. 843, col 2, para 4) Detection bias: low Data were extracted directly from information system logs; data collected was objective ‐ number of logons, etc. "Use of the personal ID allowed the Ovid system to track specific information for each of our primary and secondary outcome measures...These data were downloaded directly into a data set for analyses"
Incomplete outcome data (attrition bias) All outcomes	Low risk	"Data directly from Ovid were collected on 47 of 48 residents. The data on 1 person in the control group were lost due to a systems error" (p. 842, col 1, para 1)
Selective reporting (reporting bias)	Low risk	No protocol available, but appropriate outcomes were reported