OBJECTIVE: Long-term aim is to determine optimum interventions to reduce dental caries in children in disadvantaged communities and minimise the effects of exclusion from health care systems, of ethnic diversity, and health inequalities.

DESIGN: Generation of initial explanatory models, study protocol and development of two standardised measures. First, to investigate how parental attitudes may impact on their children's oral health-related behaviours and second, to assess how dentists' attitudes may impact on the provision of dental care.

SUBJECTS: Core research team, lead methodologists, 44 consortium members from 18 countries. To complete the development of the questionnaire, the initial set of items was administered to parents (n = 23) with children in nursery schools in Dundee, Scotland and sent to the same parents one week later. A standardised measure examining barriers to providing dental care for children aged 3 to 6 years was developed. 20 dentists working in primary dental care in Scotland completed the measure on two different occasions separated by one week.

RESULTS: Explanatory models were developed. Family questionnaire: test-retest reliability excellent (r = 0.93 p < or = 0.001) with very good internal reliability (alpha = 0.89). Dentists questionnaire: excellent test-re-test reliability r = 0.88, (alpha = 0.90).

CONCLUSIONS: Interaction between consortium members enhanced the validity of the questionnaires and protocols for different cultural locations. There were challenges in developing and delivering this multi-centre study. Experience gained will support the development of substantive trials and longitudinal studies to address the considerable international health disparity of childhood dental caries.