To evaluate the validity and reliability of the telephone-administered long IPAQ version.
The questionnaire was administered by telephone to adults on days 1 and 6. On day 1, the same questionnaire was administered by face-to-face interview, and accelerometers were delivered to subjects. Reliability was measured by comparing data collected using the telephone questionnaire on days 1 and 6. Validity was measured by comparing the telephone questionnaire data with (a) face-to-face questionnaire and (b) accelerometry.
Data from all instruments were available for 156 individuals. The Spearman correlation coefficient for telephone interview reliability was 0.92 for the leisure-time section of IPAQ, and 0.87 for the transport-related section of IPAQ. The telephone interview reliability kappa was 0.78. The Spearman correlation between the telephone-administered and the face-to-face questionnaire was 0.94 for the leisure-time and 0.82 for the transport-related section. The kappa was 0.69. There was a positive association between quartiles of accelerometer data and total telephone-administered IPAQ score (P < .001). The Spearman correlation was 0.22.
The telephone-administered IPAQ presented almost perfect reliability and very high agreement with the face-to-face version. The agreement with accelerometer data were fair for the continuous score, but moderate for the categorical physical activity variables.
Hallal and Azevedo are with the post-graduate program in Epidemiology, Federal University of Pelotas, Brazil. Simoes and Pratt are with the Centers for Disease Control and Prevention, Atlanta, GA. Reichert is with the Universidade Estadual de Londrina, Brazil. Ramos is with the Universidade Federal de São Paulo, Brazil. Brownson is with the Prevention Research Center in St. Louis, George Warren Brown School of Social Work, Dept of Surgery, and Siteman Cancer Center, Washington University School of Medicine, Washington University in St. Louis, MO.