To holistically evaluate the extent of implementation of dietary guidelines in schools and present various monitoring systems.

The study comprises three methods: (i) a cross-sectional survey (process evaluation); (ii) an indicator-based evaluation (menu quality); and (iii) a 5 d weighed food record of school lunches (output evaluation).

Slovenian primary schools.

A total 234 food-service managers from 488 schools completed a self-administrated questionnaire for process evaluation; 177 out of 194 randomly selected schools provided menus for menu quality evaluation; and 120 school lunches from twenty-four schools were measured and nutritionally analysed for output evaluation.

The survey among food-service managers revealed high levels of implementation at almost all process evaluation areas of the guidelines. An even more successful implementation of these guidelines was found in relation to organization cultural issues as compared with technical issues. Differences found in some process evaluation areas were related to location, size and socio-economic characteristics of schools. Evaluation of school menu quality demonstrated that score values followed a normal distribution. Higher (better) nutrition scores were found in larger-sized schools and corresponding municipalities with higher socio-economic status. School lunches did not meet minimum recommendations for energy, carbohydrates or dietary fibre intake, nor for six vitamins and three (macro, micro and trace) elements.

The implementation of the guidelines was achieved differently at distinct levels. The presented multilevel evaluation suggests that different success in implementation might be attributed to different characteristics of individual schools. System changes might also be needed to support and improve implementation of the guidelines.