Self-report INH adherence measures were reliable and valid in Latino adolescents with latent tuberculosis infection.
OBJECTIVE
To test the reliability and validity of 8-day and 30-day self-report measures of adherence to daily isoniazid (INH) for treatment of latent tuberculosis infection (LTBI).


METHODS
Participants were 286 Latino adolescents (ages 13-18, 55.6% male) with LTBI recruited from 10 public middle and high schools in San Diego County. INH adherence was measured monthly for up to 9 months by interview and urine specimens at unannounced visits. Reliability and validity analyses were performed within 5 consecutive months. Reliability was assessed by correlating: (1) 8- and 30-day INH adherence measures within each month; and (2) each of the two adherence measures across months. Validity was assessed by correlating reported measures with biological assays within each month.


RESULTS
Reliability tests yielded significant correlation coefficients (p < .05 to .001), both across measures (r = 0.71-0.93) and across time (r = 0.29-0.64 for 8-day recall; r = 0.32-0.69 for 30-day recall). Validity tests of both adherence measures were also significant (p < .05 to .001): 8-day recall (r(pb) = 0.52-0.72) and 30-day recall (r(pb) = 0.37-0.71).


CONCLUSIONS
Results suggest that impromptu recall measures of INH adherence, combined with urine collection, are reliable and valid in Latino adolescents.
Blumberg
Elaine J
EJ
Center for Behavioral Epidemiology and Community Health, Graduate School of Public Health, San Diego State University, CA 92123, USA. eblumberg@projects.sdsu.edu
Hovell
Melbourne F
MF
Kelley
Norma J
NJ
Vera
Alicia Y
AY
Sipan
Carol L
CL
Berg
Jill P
JP
D000293:Adolescent; D000294:Adolescent Behavior; D000995:Antitubercular Agents / Q000008:administration & dosage*; D030881:Disclosure / Q000592:standards*; D005260:Female; D006630:Hispanic or Latino / Q000523:psychology*; D006801:Humans; D007538:Isoniazid / Q000008:administration & dosage*; D008297:Male; D010349:Patient Compliance; D015203:Reproducibility of Results; D014376:Tuberculosis / Q000188:drug therapy*
D000995:Antitubercular Agents; D007538:Isoniazid