Nutrition Guidance by Primary-Care Physicians: LISREL Analysis Improves Understanding

Abstract

1 G e r r it J. H id d in k , P h .D .,* '2 J o s e p h G. A. J. H a u t v a s t , M .D .,t C e e s M . J. v a n W o e r k u m , P h .D .,$ C a r e l J. F ie r e n , M.D., § a n d M a r t in A . v a n 't H o f , P h .D .ÎI Nutrition and Health, Zonnebaan 12D, 3606 CA Maarsaen, the Background. When determ inants of nutrition guid ance practices for primary care physicians (PCPs) are id en tified, the key q u estion rem ains: w hat is th e mechanism of action? This knowledge is essential in order to understand how PCPs practice n u trition guidance. * Daily Foundation forMethods. Mail questionnaires (result of focus-group discussions and in-depth interview s) were sent to a nationwide random sample of 1,000 PCPs in the N eth erlands, who had been in practice for betw een 5 and 15 years (633 respondents). The m echanism of action o f determ inants of nutrition guidance practices of PCPs was identified by means of linear structural relation ship analysis (LISREL) using a postulated model.Results. The postulated model on the mechanism of action was confirmed. The model demonstrates that nutrition guidance practices of PCPs are directly and significantly based on a few predisposing factors; driv ing forces and perceived barriers may act as signifi cant intermediary variables. The predisposing factors, driving forces, and perceived barriers were identified.Conclusion. Policies to improve nutrition guidance practices of PCPs may, in the future, benefit from a LISREL model analysis of determ inants of these prac tices to become more effective. Using multiple regres sion analysis to ascertain the determ inants of these practices could result in m issing important predispos ing factors and "hidden" interm ediary factors and lead, therefore, to an incom plete understanding of the mechanism of action. © lf)97 A cad em ic P ro sa

The NECTAR-Study: development of nutrition modules for general practice vocational training; determinants of nutrition guidance practices of GP-trainees

“…As a ®rst step in the analysis of the questionnaire, we computed determinants of nutrition guidance practices of GP-trainees by using items from the questionnaire as pointed out by Hiddink (1997b) and measured reliability of these factors. Secondly, we used LISREL model analysis as the analysis of choice (Hiddink et al, 1997b;Jo Èreskog & So Èrbom, 1989) to obtain a GP-trainee-model of the mechanism of action of these determinants (Green & Kreuter, 1991).…”

“…Secondly, we used LISREL model analysis as the analysis of choice (Hiddink et al, 1997b;Jo Èreskog & So Èrbom, 1989) to obtain a GP-trainee-model of the mechanism of action of these determinants (Green & Kreuter, 1991). The same nutrition guidance practices as tested in the GP-study (`extent of nutrition education and information' and`noticing patients' overweight and guidance of treatment') were tested as dependent variables in this study (Hiddink et al, 1997b). The variable`extent of nutrition education and information' was scored in one question on a 5-point Likert-type scale, ranging form`not at all' to`very intense'.…”

“…Factors were de®ned as sums of items, as pointed out by Hiddink (1997b), standardised for scale width. Crohnbach's alpha was used as an indication of reliability of computed factors.…”

“…We hypothesised that the GP-model of the mechanism of action of determinants (predisposing factors, driving forces and barriers) found in previous studies (Hiddink et al, 1997b), would also apply to GP-trainees.…”

“…Lack of nutrition training and education among Dutch GPs has been assessed in previous investigations (Hiddink et al, 1995). This lack not only forms a barrier perceived by GPs, but also acts as a barrier to the extent of nutrition education and information given by GPs (Hiddink et al, 1997b). As has been stated by the Dutch Nutrition Foundation, nutrition topics are rarely found in the basic medical education curricula as well as in the curricula of the University Departments for Vocational Training in the Netherlands (van Binsbergen et al, 1997).…”