“…However, one study, although formally classified as methodologically ‘acceptable’ [15], was excluded from the following review because of the inadequately operationalized comparison group and because of the low numbers of tuberculin test conversions (n = 30). All methodologically ‘inadequate’ studies [13,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52] were excluded from the following review. In this review, no statistical meta-analyses were performed, as there were large differences among the studies of adequate methodologic quality.…”