Design: Cluster randomized trial, controlled and multicentric, comparing one group of patients that take part in the Health Workshops, with another group of similar characteristics that don't.
Setting: The study will be done in Heath Care Centers of Barcelona City.
Randomization unit: Primary care Teams (PCT)
Study Population: Population around the Centers that participate in the Study and that meet the criteria of inclusion.
• Persons of both sexes between 18 and 65 who consent to do so.
• If there is an objection to participating during a period of 12 months.
• If there a language difficulty, unable to understand or express in Spanish or Catalan.
• If there are acute mental problems.
• Other health problems which may be a difficulty in following the workshop, (like terminals, organic pathology...).
Sample size calculation: Accepting an Alfa risk of 0.05 and a Beta risk of 0.2 in a bilateral contrast, 108 individuals per group are needed in order to detect how statistically effective it is in a 20% difference between groups in quality of life with the SF-36 Questionnaire. We have estimated a 10% rate of loss in participation. The ARCOSENO approximation has been used.
Variables in the study: We collect socio-demographic variables from all participants: age, sex, studies, employment or work situation.
Principal Variable: HRQOL measured by means of SF-36 Questionnaire. We have selected the quality of life perceived indicator as the main variable as it is sensible to small changes [19
Variables related to the intervention:
• Number of sessions the person has attended.
• IPAC Questionnaire for variables related to physical activity (the IPAC questionnaire has been used in research around this area so it allows us to compare the data obtained.)
• The variables related to eating habits will be collected by means of Questionnaire PREDIMED [15
], which is validated and used in our area, as so allow us to compare results.
• Blood Pressure, Lipid Profile, Height, Weight, will be gathered from the computerized clinical history.
• To estimate the costs we will add the time spent by professionals directly related with the intervention (telephone calls, meetings with participants, gathering of data, workshops...)
• Gathering of information: the gathering of data will be done in both groups, (intervention and control groups): before each intervention (Health Workshop), at the end of the intervention and in 6 months and 12 through self administered questionnaires in Teleform© format.
Description of the Study (Figure )
The stages of this study are the following:
Phase Recruitment and selection:
1 The recruitment of the PCT: The project is explained to professionals belonging to the Health Centre. Those interested in participating in the recruiting of patients will sign a commitment of participation in the Project. The participants will be recruited by these professionals and their inclusion will be consecutive. Once the recruitment has ended, the groups will be randomized in the intervention or control group. Persons interested will fill up an application form for the Workshop, which will be available in their Health Care Center (HCC) and where they have to give their name, phone number, and time availability.
The Blood Pressure (BP) and Weight data will be gathered (in those persons who consent), at an individual visit after the informative meeting. They will be asked to have a Lipid Profile (if it is not available in their clinical history in a 3 months period before the workshops begins), and again after 12 months.
Phase The Forming of the Study Groups
2 Based on the persons who have given their consent to participate, an random assignation to one or another group will take place, and the workshops will then start (with groups of 12 to 15 persons in each).
Phase Intervention (only in the group intervened)
3 The group intervention then starts in 8 sessions in which life activities will be approached in a progressive manner. During the sessions, tools will be offered to increase knowledge and develop abilities and motivations that help with life activities and the progressive incorporation of healthy habits. At the end of each session support material will be handed out with the session's contents and indications of activities to practice during the week.
The workshops will be offered at different schedules to facilitate assistance. The contents of the sessions are in Table .
Subject matter of the sessions in the work shop
We have elaborated specific material, (with slides and points dealt with in the sessions) to ensure the unification of the message given. Also, we have elaborated support and reminder material for each session which gathers all the contents of the sessions. Such material is handed out at the end of each session to be kept in the files provided at the beginning of the Health Workshop, and which will, in the end, form a Manual for Health Self-Care and Maintenance.
The control group will continue to receive normal attention and will have the possibility, if they so desire, of doing the Health Workshops at the end of the Project, (if it has proven effective), once the 12 months are over with the last evaluation.
Phase Closing of the Project
4 Gathering and analyzing the last data and communicating the results.
The analysis will be done on an intention to treat basis. Those who have done less than six sessions will be considered withdrawals.
The descriptive analysis will be done in proportion to the quality variables and the average values for the quantities, with the corresponding measures of dispersion.
To observe the effect of the intervention in quality of life related to health, the change of habits and the costs derived from related resources, the T-Tests will be used for paired data and the McNemar Test or equivalents for quantitative or qualitative variables or their non parametric equivalents, if the distribution of the variable does not comply with the criteria of normality (Kolmogorov-Smirnof).
To analyze the factors that have influence over the changes of quality of life related to health (CVRS) and those related with the intervention, models of multiple regressions will be used. In each regression model the dependent variable will be derived from the calculation or the difference between ratings in the beginning of the study and the ratings at the end of the SF-36; the rest of the variables determined in the study will be included as independent variables. As the first step in the analysis of regression the adequate diagnosis will be done to detect extreme values and verify conditions of applicability (homocedastisity, normality and independence of waste). If needed the necessary transformations will be done in the dependent variables for the fulfillment of applicability conditions. The criteria of selection of variables for the estimation of multivariable models will be a Forward-Stepwise with the criteria of input of p < 0.05 and a criteria of output of p > 0.10.
The proceedings used to guaranty the quality of the information are the following:
• The intervention is done by the persons in the research group who created all the educational material being used in the session, which guarantees a homogenous intervention.
• The gathering of data is done through self-operated questionnaires in Teleform©. This automated software that reads scanned questionnaires, performs a validating process of the data with previously established parameters, and once the data is validated these are poured into a specifically created database.
• The introduction of information or data will be performed by a person hired to provide technical assistance for this study.
It will be an indispensable requisite to participate in this study that all participants sign their informed consent. The same document specifies that the participation has to be voluntary, with the possibility of leaving the program if he or she so desires, and that the intervention will not have a negative effect in their health care assistance. They will be given both oral and written information. The subjects will have opportunities to ask questions about any detail of the study.
The protocol has been evaluated by the Ethical Committee in Clinical Investigation (CEIC) of the Research Institute of Primary Attention (IDAP) Jordi Gol and counts with its approval.
Confidentiality of the information: only the researchers will have access to the data of the subjects who accept. Once the study is finished, both the control group and the group intervened will be informed of the results; once the effectiveness of the Health Workshop is proven, they will be invited to participate.