Table 7 Research questions for future systematic reviews related to health inequalities

1. How does the effectiveness of interventions to effect positive changes in health behaviours vary according to the socio-economic, cultural or other characteristics of participants? This might include studies of effectiveness according to age, gender, ethnicity, social class and locality.

2. What is the effectiveness of interventions which address the interconnectedness of negative health behaviours? For instance, this review might explore the effectiveness of combined smoking and alcohol reduction/cessation interventions.

3. What is the demographic profile of those who gain access to interventions and how does this relate to existing knowledge on health inequalities? This review could explore the socio-economic characteristics of intervention participants to reveal the 'fit' between those groups most at risk from the ill effects of negative health behaviours and intervention participants.

4. What are the challenges for recruitment of intervention participants? What are the most effective ways of recruiting 'hard to reach' groups, such as ethnic minorities and the socially and economically disadvantaged?

5. What is the relationship between the outcomes of interventions and the social, cultural and demographic characteristics of participants? Questions to explore might include whether the intervention is equally effective with participants who differ with regard to gender, age, ethnicity, rural or urban location, and employment status.