Almomani 2006.

Methods	Allocation: randomised Blinding: not clearly described and tested Duration: 4 weeks, assessed at baseline and after 4 weeks Design: parallel Setting: Wyndott Center for Community and Behavioral Health, Kansas City, Kansas, USA
Participants	Diagnosis: self reported and confirmed by medical reports History: severe mental illness (schizophrenia, schizoaffective disorder, bipolar disorder, and depression) N = 50 Age: 19 to 61 years Sex: 27F, 23M Inclusion criteria: severe mental illness, between the ages of 19 and 61 years, with a minimum of 1 gradeable tooth in each sextant Exclusion criteria: obvious periodontal disease, participants with orthodontic appliances, pregnancy, mental retardation, severe hearing or visual problems, major neurological illness, people with dementia, people with guardians or inability to comply with the study protocol, people who do not have a mobile and/or regular phone, and people who are currently using a mechanical toothbrush
Interventions	1. Oral health education and instruction in tooth brushing using a mechanical toothbrush, and environmental supports for creating a habit pattern. N = 25* 2. Only a mechanical toothbrush. N = 25*
Outcomes	Dental state: plaque index scores** Leaving the study early* Unable to use: Quality of life/satisfaction ‐ questionnaire (not reported by group)
Notes	*We had to assume that 25 were allocated to each group; this seems to be confirmed by the final numbers in the analysis within the paper, correlated with the total numbers lost to follow‐up ‐ not reported by group of allocation. **It remains unclear as to whether these scores are endpoint or change. We have treated as if they are change. In addition, standard deviations are reported that are so narrow we are concerned that they are really standard errors. However, we have entered them as standard deviations
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: ''All the participants were randomly assigned to one of two treatment groups (A,B) by using a random numbers table'' Response: low risk
Allocation concealment (selection bias)	Unclear risk	Quote: "...using a random numbers table" Response: unclear method of concealment
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	"This study used a randomised, controlled examiner blind, parallel design" Response: It is unclear whether the participants were blind to their allocation
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Insufficient information
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Quote: ''Fifty participants were recruited for this study, 42 (84%) completed the study. Eight participants dropped out of the study..." Response: no data from those who left early
Selective reporting (reporting bias)	High risk	Plaque index scores were listed clearly, but the other outcomes including leaving the study early, unable to use toothbrush, quality of life/satisfaction ‐ questionnaire were not reported clearly
Other bias	Unclear risk	Quote: "...support for this article was approved by a grant from Proctor and Gamble company" Response: This company produced Crest Spinbrush Pro toothbrushes, but we are unclear what effect this would have on the results