Study designs of evaluations included in the review
Randomised controlled trials (RCTs) which had fewer than four flaws in eight general quality criteria (covering randomisation, blinding, exclusion criteria and statistical procedures), and fewer than twelve flaws in eighteen treatment-specific quality criteria (covering documentation, specification of treatment, prevalence, standardisation and adverse event reporting). These criteria were developed after having inspected the trials, to measure susceptibility to bias.
Specific interventions included in the review
Topical treatments for killing lice. Most trials evaluated single applications of the treatments. Compounds (in lotion and/or shampoo form) included in trials were: carbaryl; lindane; malathion; permethrin; pyrethrines (bioresmethrin, chlorphenamide, pyrethrin).
Participants included in the review
People infested with head lice in the community or schools were included.
Outcomes assessed in the review
The outcome assessed was the absence of live lice and viable nits on day 14 after treatment (determined by visual inspection).
How were decisions on the relevance of primary studies made?
The authors do not state how the papers were selected for the review, or how many of the authors performed the selection.