Table 1.

Study Participation at Practices and LHDs

ParticipationPracticesLHDs
n(%)n(%)
Total eligible793(100.0)561(100.0)
Full participation
 Questionnaire completed;
 analyzable blood
460(58.0)285(50.8)
Partial participation
 Questionnaire completed;
 blood not drawn
137(17.3)239(42.6)
 Questionnaire completed;
 blood drawn but not analyzable
14(1.8)5(0.9)
 No questionnaire; blood analyzed22(2.8)1(0.2)
 Questionnaire completed;
 confirmatory blood not drawn
4(0.5)15(2.7)
 Questionnaire completed;
 confirmatory blood analyzed
 at other laboratory
6(0.7)0(0.0)
No participation
 Missed or refused150(18.9)16(2.9)