Public Health Nutrition

Research Article

Who eats four or more servings of fruit and vegetables per day? Multivariate classification tree analysis of data from the 1998 Survey of Lifestyle, Attitudes and Nutrition in the Republic of Ireland

Sharon Friela1 c1, John Newella2 and Cecily Kellehera3

a1 Centre for Health Promotion Studies, National University of Ireland, Block T, Distillery Road, Galway, Republic of Ireland

a2 Department of Mathematics, National University of Ireland, Galway, Republic of Ireland

a3 Department of Epidemiology and Public Health Medicine, University College Dublin, Republic of Ireland


Objective To identify, using the novel application of multivariate classification trees, the socio-economic, sociodemographic and health-related lifestyle behaviour profile of adults who comply with the recommended 4 or more servings per day of fruit and vegetables.

Design Cross-sectional 1998 Survey of Lifestyle, Attitudes and Nutrition.

Setting Community-dwelling adults aged 18 years and over on the Republic of Ireland electoral register.

Subjects Six thousand five hundred and thirty-nine (response rate 62%) adults responded to a self-administered postal questionnaire, including a semi-quantitative food-frequency questionnaire.

Results The most important determining factor of compliance with the fruit and vegetable dietary recommendations was gender. A complex constellation of sociodemographic and socio-economic factors emerged for males whereas the important predictors of 4 or more servings of fruit and vegetable consumption among females were strongly socio-economic in nature. A separate algorithm was run to investigate the importance of health-related lifestyle and other dietary factors on compliance with the fruit and vegetable recommendations. Following an initial split on compliance with dairy recommendations, a combination of non-dietary behaviours showed a consistent pattern of healthier options more likely to lead to compliance with fruit and vegetable recommendations. There did, however, appear to be a compensatory element between the variables, particularly around smoking, suggesting the non-existence of an exclusive lifestyle for health risk.

Conclusions Material and structural influences matter very much for females in respect to compliance with fruit and vegetable recommendations. For males, while these factors are important they appear to be mediated through other more socially contextual-type factors. Recognition of the role that each of these factors plays in influencing dietary habits of men and women has implications for the manner in which dietary strategies and policies are developed and implemented.

(Received April 20 2004)

(Accepted August 11 2004)


c1 *Corresponding author: Email