Do general practitioners act consistently in real practice when they meet the same patient twice? Examination of intradoctor variation using standardised (simulated) patients.

OBJECTIVE: To assess the variation within individual general practitioners facing the same problem twice in actual practice under unbiased conditions.
DESIGN: General practitioners were consulted during normal surgery hours by a standardised patient portraying a patient with angina pectoris. Six weeks later the same general practitioners were consulted again by a similar standardised patient portraying a similar case. The patients reported on the consultations.
SETTING: Trondheim, Norway.
SUBJECTS: Of 87 general practitioners invited by letter, 28 (32%) agreed to participate without hesitation; nine others (10%) wanted more information before consenting. From these 24 were selected and visited. MAIN OUTCOME MEASURES: Number of actions undertaken from a guideline in both rounds of consultations. Duration of consultations.
RESULTS: The mean (range, interquartile range) guideline score, total score, and duration of consultation were not significantly different between the first and second patient encounters for the group as a whole. For individual doctors the mean (SD) difference was -0.09 (3.36) for the guideline score, 0.30 (8.1) for the total score, and -0.87 (9.01) for consultation time.
CONCLUSIONS: The study shows that assessment of performance in real practice for a group of general practitioners is consistent from the first round of consultations to the second round. However, significant variation occurs in performance of individual physicians.