Skinner 2013.

Methods	FLUOROSIS STUDY Country of study: Australia Geographic location: New South Wales Year of study: 2010 Year of change in fluoridation status: NA Study design: cross‐sectional
Participants	Inclusion criteria: school students aged 14‐15 years under the jurisdiction of the NSW Department of Education and Training, the Catholic Education Commission and Independent Schools Exclusion criteria: not stated Other sources of fluoride: not stated Ethnicity: aboriginal status was coded from parental responses (not reported by fluoridation status) Social class: self‐reported family income data were provided by parents or guardians and was used as a measure of SES (not reported by fluoridation status) Residential history: not stated Other confounding factors: not stated
Interventions	Group 1: fluoridated (artificial; ppm not specified) Group 2: non‐fluoridated
Outcomes	Dental fluorosis (TF); caries data also evaluated within the study but excluded from review due to study design Age at assessment: 14 and 15 years
Funding	The Centre for Oral Health Strategy NSW
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Sampling	Low risk	Quote: "random sample"
Confounding	Low risk	Quote: "initial weights were adjusted to ensure the distribution of the sample reflected the regional population distribution of 14‐15‐year‐olds in NSW"
Blinding of outcome assessment (detection bias) All outcomes	High risk	Insufficient information
Incomplete outcome data (attrition bias) All outcomes	High risk	Particpation rate low (23%). Did not account for all participants in analysis
Selective reporting (reporting bias)	Unclear risk	Observed enamel fluorosis/defects were recorded for both the central incisors; not all data reported
Other bias	Unclear risk	No other apparent bias