Use of surgical face masks to reduce the incidence of the common cold among health care workers in Japan: a randomized controlled trial.
BACKGROUND
Health care workers outside surgical suites in Asia use surgical-type face masks commonly. Prevention of upper respiratory infection is one reason given, although evidence of effectiveness is lacking.


METHODS
Health care workers in a tertiary care hospital in Japan were randomized into 2 groups: 1 that wore face masks and 1 that did not. They provided information about demographics, health habits, and quality of life. Participants recorded symptoms daily for 77 consecutive days, starting in January 2008. Presence of a cold was determined based on a previously validated measure of self-reported symptoms. The number of colds between groups was compared, as were risk factors for experiencing cold symptoms.


RESULTS
Thirty-two health care workers completed the study, resulting in 2464 subject days. There were 2 colds during this time period, 1 in each group. Of the 8 symptoms recorded daily, subjects in the mask group were significantly more likely to experience headache during the study period (P < .05). Subjects living with children were more likely to have high cold severity scores over the course of the study.


CONCLUSIONS
Face mask use in health care workers has not been demonstrated to provide benefit in terms of cold symptoms or getting colds. A larger study is needed to definitively establish noninferiority of no mask use.
Jacobs
Joshua L
JL
University of Hawaii John A. Burns School of Medicine, Honolulu, HI; St. Luke's Life Science Institute Center for Clinical Epidemiology, Tokyo, Japan. Electronic address: jjacobs@hawaii.edu.
Ohde
Sachiko
S
St. Luke's Life Science Institute Center for Clinical Epidemiology, Tokyo, Japan.
Takahashi
Osamu
O
St. Luke's Life Science Institute Center for Clinical Epidemiology, Tokyo, Japan; St. Luke's International Hospital, Tokyo, Japan.
Tokuda
Yasuharu
Y
St. Luke's Life Science Institute Center for Clinical Epidemiology, Tokyo, Japan; St. Luke's International Hospital, Tokyo, Japan.
Omata
Fumio
F
St. Luke's Life Science Institute Center for Clinical Epidemiology, Tokyo, Japan; St. Luke's International Hospital, Tokyo, Japan.
Fukui
Tsuguya
T
St. Luke's Life Science Institute Center for Clinical Epidemiology, Tokyo, Japan; St. Luke's International Hospital, Tokyo, Japan.
D000328:Adult; D003139:Common Cold / Q000453:epidemiology / Q000517:prevention & control*; D003428:Cross Infection / Q000517:prevention & control* / Q000635:transmission; D004209:Disposable Equipment; D005260:Female; D006282:Health Personnel; D006746:Hospital Bed Capacity, 500 and over; D006801:Humans; D017053:Infection Control / Q000295:instrumentation*; D007564:Japan / Q000453:epidemiology; D008297:Male; D008397:Masks; D008875:Middle Aged; D011446:Prospective Studies; D012134:Respiratory Protective Devices