444 Review of critical appraisal tools for NHPs Database searches and hand searching 4442 citations reviewed 410 abstracts reviewed 29 articles reviewed 16 instruments 4032 citations excluded: not relevant 381 abstracts excluded: not relevant 13 articles were excluded because instrument: - was intended for therapies other than NHPs: 6 -was published in more than one source: 5 - was not designed for RCTs: 1 - was not published: 1 6 checklists 3 rating scales 3 combination scales and checklists 4 numeric scales Figure 1. Results of literature search and relevance assessment. therefore was not useful for the other non-herbal types of NHPs and there was no indication that the CONSORT Statement for Herbal Interventions had been validated for use as an instrument for critically appraising an RCT. There was a wide variety in the number and wording of the items included in the identified appraisal instruments. As well as the items contained in the CONSORT Statement for Herbal Interventions, an additional 12 unique miscellaneous items were extracted from the instruments. This illustrated the lack of apparent consensus on which items are essential for inclusion in a critical appraisal instrument. Encouragingly, there was evidence that the most common items found (e.g. randomization sequence generation (31) blinding (31–34), allocation concealment (31–33) and participant flow (35–37) have been shown to be important in minimizing bias in trials and/or in improving the quality of reporting. Additionally, each of these items was part of validated instruments used with conventional medica- tions (38–41). This provides good rationale for inclusion of items in critical appraisal instruments. Surprisingly, seven of the 16 instruments developed for use with NHPs did not contain any items to address the identity and content of the NHPs being tested. An adequate appraisal of the design and results of an RCT of an NHP must include an assessment of the informa- tion provided in the report of the RCT detailing the identity and chemical content of the NHP tested in the trial. Documenting the name of the NHP that was evaluated is not always sufficient to ensure unambiguous identity of the NHP, as it is well known that the chemical