Table 2

 Methodological quality of included studies

StudyInclusion/exclusion criteriaRandomisationMasking of examinersCompleteness of follow up
Van der Elst et al10Clearly statedNot clearly statedExaminer was masked to intervention statusExact percentage follow up at 8 months not stated
Goldberg et al11Clearly statedNot clearly statedExaminers were masked to intervention statusThere was complete follow up in the treated; 60% untreated
Black et al12Clearly statedDrawing a card from deck generated by a random number tableUnclearTwo year follow up of 62%. Some data provided on failure of follow up. 7 year follow up of 49/93.
Bada et al13Clearly statedNot clearly statedExaminers were masked to intervention statusFollow up was 67%
Ratrisawadi et al14Clearly statedAlternate assignmentUnclearFollow up was 38%