Adaption and reliability of the Nutrition Environment Measures for stores (NEMS-S) instrument for use in urban areas of Chile

OBJECTIVE: To adapt and assess reliability of the Chilean version of Nutritional Environment Measurement for Stores (NEMS-S-CHILE) to measure the food environment of stores in urban areas. DESIGN: NEMS-S-CHILE was the NEMS-S tool adapted to the Chilean food patterns; foods were grouped according to level of processing in (a) unprocessed or minimally processed foods, (b) processed culinary ingredients, (c) processed foods, and (d) ultra-processed foods, and scored according to NEMS-S-CHILE tool. Reliability inter evaluators was measured. SETTING: City of Concepción, Bio-Bio region, Chile. PARTICIPANTS: Seventeen of a total of 25 supermarkets, and 9 out of 10 street markets according to the municipal registry and the street market trade unions, representing 74.3% of both types of food premises in Concepción. RESULTS: Reliability inter evaluators was measured by the following aspects: product availability, price, quality, and variety, through the intraclass correlation coefficient (ICC), percent agreement, and Cohen’s kappa analysis. Reliability was high for availability, where the kappa index and ICC were acceptable, ranging from moderate to high (0.42 to 1.00 for the kappa coefficient and 0.65 to 1.00 for ICC), as well as for prices (ICC: 0.65-1.00 ), variety (kappa: 0.76-1.00) and quality (percent agreement: 68.2- 100%). CONCLUSIONS: The adapted instrument, NEMS-S-CHILE, has a high reliability inter evaluators and can be useful to measure the availability of foods by the level of processing according to the prevalent food system in developing countries. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12889-022-12651-w.