Int. J. Environ. Res. Public Health 2010, 7 14 financial hardship as the main motivating factor [76]. Further, for such part-time students, research has shown significant differences between full- and part-time students as regards their satisfaction with their educational experience at university [77]. Economic factors as predictors for academic outcomes, however, cannot be addressed in health programmes alone, but need to be addressed at the policy macro level and politically, in terms of scholarship programmes and/or financial support programmes for disadvantaged students, or perhaps monetary incentives for high-achieving students. Interestingly, satisfaction with income was also correlated with lower importance of good grades suggesting that very high income could have diminishing effects on students‘ educational achievement. This would again support incentive systems where monetary incentives are linked to achievement. This study has limitations, and generalization of the findings requires caution. We surveyed one university in the UK. Self-reported data could be subject to recall bias, sociability and social desirability. Despite our broadening of the data collection in an attempt that the selection of students in this study would be representative of their university, our sample remains a convenience sample. Such convenience samples are not uncommon in student surveys e.g., in Hong Kong [78], in the USA [79], or Australia [80]. Similarly, in the USA, post secondary institutions (universities and colleges) self- selected themselves to participate in the American College Health Association National College Health Assessment survey [73]. Other limitations are related to the use of empirical measures of health, the endogeneity of health outcomes and their interactions with risky behaviours, and that strong positive correlations between multiple health disorders and health behaviours that might exist in the data present a major challenge for researchers interested in identifying the individual impacts of poor health conditions on academic performance [81]. In addition, one of our outcome measures (module mark) is based on the marks in only one module and does not take into account the variations of academic performance across different modules. Further research would need to explore how different health and wellbeing variables are associated with different measures of student achievement, and the mediating variables for such relationships and should attempt to statistically test the relationships suggested in the conceptual model. 5. Conclusion In conclusion, the findings from this study support a conceptual framework suggesting reciprocal relationships between health, health behaviours and educational achievement. Even when health, health awareness and health behaviour variables were not directly linked to module marks, they were associated with some of the determinants of module marks such as the importance of good grades. The results support a focus on comprehensive health programmes at universities that take into account the multiple factors influencing students‘ achievement. Comprehensive health promotion programmes may have the potential to influence relevant predictors of educational achievement in university students and therewith do not only add to population health, but contribute to the core business of higher education institutions.