Data collection and follow-up

The primary endpoints are the change in HRQoL, glycaemic control (HbA1c) and weight loss at 6 and 12 months from baseline. The data collection will be carried out simultaneously through self-administered questionnaires (quality of life, diet and physical activity) and the measurement of biological variables in both groups, intervention and comparison, before initiating the intervention, after the intervention (3 months), and 6 and 12 months after the intervention. A specific evaluation of the knowledge acquired will not be carried out, but its incorporation into the patients' lives will be reflected in the improvement of diabetes control and their quality of life. Original study questionnaires will be entered and kept on file at the participating centre or the coordinating centre. All data will be recorded by a nurse in every centre, and monthly data with any identifying participant information removed will be sent to the coordinating centre. All investigators will be given access to the cleaned datasets. Recruitment and follow-up began in September 2019, and we expect to end in September 2021.

The following data will be collected from participants, when appropriate, using validated tools at baseline, after the intervention period (3 months), and at 6 and 12 months:

EuroQol-5D (EQ-5D-3L) questionnaire.³⁷ This is a generic tool used as a measure of HRQoL. This tool obtains information through five dimensions: mobility, self-care, usual activities, pain/discomfort and anxiety/depression. Each dimension has three levels (no problems, some problems and extreme problems). This scale can be converted to a unique index. The utility index of quality of life was also created based on previous studies.^{38 39} As a result of an intervention aimed at improving the control of chronic diseases and minimising their complications, the quality of life of the people served is a main outcome.

Prevention with Mediterranean Diet (PREDIMED) questionnaire.⁴⁰ This is a tool consisting of 14 items aimed at measuring adherence to the Mediterranean diet. This indicator will allow us to assess how knowledge has been incorporated by modifying life habits related to diet.

International Physical Activity Questionnaire (IPAQ).^{41 42} IPAQ is an instrument for monitoring physical activity and inactivity. Data from the short IPAQ form will be summarised according to the physical activities recorded (walking, moderate and vigorous activities) and the estimated time spent sitting per week. Data will be used to estimate the total weekly physical activity by weighting the reported minutes per week within each activity category by a the metabolic equivalent energy expenditure estimate assigned to each category of activity. This indicator will allow us to assess the modification of lifestyle habits related to exercise.

Satisfaction Questionnaire adapted from the questionnaire of the Catalan Health Service. This is a generic tool used as a measure of satisfaction level of participants regarding the attention, instruction and material received during the intervention. Participants will be asked to complete this questionnaire to measure their satisfaction level with the provided attention in the primary healthcare centres after their T2DM diagnosis.

Patient demographics such as age, gender, marital status (single/married/divorced/widowed), cohabitation status (living alone/living with someone else), educational level (illiterate/primary/secondary/university) and employment (currently working/unemployed/retired) will be collected. The patients’ medical records will be reviewed to obtain clinical and medication histories. Further, chronic pathologies and their diagnosis dates, tobacco and alcohol consumption, and use of healthcare services in the last year will be collected at baseline and at the end of the study. We will also collect specific biological variables related to T2DM and associated comorbidities: HbA1c, weight, BMI, abdominal perimeter, blood pressure and cholesterol. All these variables will allow us to determine the clinical impact of this project.