The effects of acute sleep deprivation on performance of medical residents in a regional hospital: prospective study.

OBJECTIVE To evaluate the effects of acute sleep deprivation on the level of perceived occupational stress and cognitive functioning in a group of medical residents. DESIGN Prospective study. SETTING Regional hospital, Hong Kong. PARTICIPANTS Twenty-one residents who had regular in-hospital on-call duties. MAIN OUTCOME MEASURES From January to April 2002, participants were asked to complete the Raven Advanced Progressive Matrices (sets I and II) and Occupational Stress Inventory-Revised tests at the beginning of an on-call day. They then repeated the tests towards the end of their on-call duties on their next on-call day, at a mean (standard deviation) interval of 8.9 (2.3) days. Occupational Stress Inventory-Revised test scores were transformed into T-scores to provide information about an individual's scores relative to the scores of participants in a normative sample. RESULTS The group slept for a mean (standard deviation) of 2.9 (1.0) hours during 29.3 (3.8) hours of on-call duties. Before the on-call duties, participants' mean T-scores for the Occupational Stress Inventory-Revised test ranged from 50.6 to 54.5 for the Occupational Role Questionnaire, 52.0 to 57.0 for the Personal Strain Questionnaire, and 37.3 to 52.3 for the Personal Resources Questionnaire. After on-call duties, apart from a slight increase in Role Insufficiency T-scores (50.6 [5.9] versus 52.1 [6.0]; P=0.044), there was no significant change in all other scales of the Occupational Stress Inventory-Revised test. The scores of the Raven Advanced Progressive Matrices test remained stable after the on-call duties (11.3 [1.2] versus 11.5 [0.8], P=0.129 for set I; 29.9 [5.5] versus 30.2 [6.3], P=0.2 for set II). CONCLUSION Acute sleep deprivation among medical residents was not associated with any significant changes in both cognitive functioning and level of stress perceived.