Condition category
Nutritional, Metabolic, Endocrine
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status

Plain English Summary

Background and study aims
Weight loss surgery, also called bariatric surgery, is a drastic measure used to help people who are dangerously overweight. There are a number of different types of bariatric surgery; however they all work by limiting the amount a person can eat or reducing the number of calories that are absorbed from food. Although these procedures can be very effective for losing weight in the short-term, many people put back on the weight they have lost in the long-term. There is a strong link between behaviour after surgery and the long-term outcomes, as people who fall back into old habits, such as overeating or an unhealthy diet, are unlikely to maintain their weight loss. Support groups to help people to stick to their weight loss plans after surgery have been suggested, however the feasibility of this has been questioned due to costs and limited human resources. One way of resolving these issues is by offering this support online. APOLO-Bari is an internet based programme which has been developed to help bariatric surgery patients to maintain their weight loss long-term. The aim of this study is to test the effectiveness of this programme in preventing weight regain after bariatric surgery.

Who can participate?
Adults with more than 30% post-operative weight loss.

What does the study involve?
Participants are randomly allocated into one of two groups. The first group (intervention group) receives full access to the APOLO-Bari programme. This includes a self-help manual, designed to educate people about behaviour, a weekly feedback monitoring system and interactive chat sessions with a trained psychologist. After 12 months access to the programme, participants will not be able to access it for a further 12 months (follow up period). The second group (control group) has no access to APOLO-Bari throughout the study, and participants are only able to access general information about obesity and bariatric surgery. Both groups complete questionnaires at the start of the study, every fourth month until the end of the intervention period, and then at 6 months and 12 months in the follow up period.

What are the possible benefits and risks of participating?
Benefits of participating include the free support from APOLO-Bari, which should help patients to lose more weight and not regain weight. There are no risks of participating in the study.

Where is the study run from?
1. Hospital de Braga (Portugal)
2. Hospital de São João (Portugal)

When is the study starting and how long is it expected to run for?
July 2011 to August 2014

Who is funding the study?
Foundation for Science and Technology (Portugal)

Who is the main contact?
Dr Eva Conceicao

Trial website

Contact information



Primary contact

Dr Eva Conceicao


Contact details

School of Psychology
Univertsity of Minho
Campus Gualtar
+351 917 853236

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

APOLO-Bari: an internet-based program for longitudinal support of bariatric surgery patients. A multicenter randomized controlled trial



Study hypothesis

The specific objectives of this project are:
1. To test short- and long-term efficacy of the program in preventing weight regain and promoting weight loss maintenance; promoting adjusted eating behaviors; decreasing psychological distress; enhancing individual self-concept and other psychological outcomes.
2. To test the utility, feasibility and satisfaction perceived with APOLO-Bari in terms of compliance to proposed tasks, log-in frequency and direct evaluation of satisfaction of participants. Participants with higher login frequencies and compliance to monthly assessments are expected to report better weight outcomes; higher levels of satisfaction with weight loss and surgical treatment; and lower levels on the self-reported measures, reflecting a better psychosocial functioning.
3. To study weight regain exploring the temporal courses of eating related features and predictors of weight regain. We expect to identify fluctuations in key-behaviors that precede weight regain.

Ethics approval

1. Ethics Subcommittee for Life and Health Sciences, University of Minho, 21/04/2015, ref: SECVS 018/2015
2. Hospital de Braga ethics committee, 08/09/2015, ref: CESHB044/2015

Study design

Randomized controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet




Those accepting entering the study will have a computer connected to the internet to their availability to accept the informed consent form online and register by creating a personal username and password. All participants respond an initial short socio-demographic and clinical questionnaire. To ensure the concealment of allocation, the system will then automatically randomize participants on a 1:1 basis, matching for age, gender and surgery type.

Intervention Group (IGroup): Receives full access to the the 3 components of APOLO-Bari program in their personal account. Intervention will last for 12 months and a 12 months period follows with no access possible to the program. During the intervention period the system will record data on login frequency, task submission and weekly monitoring from IGroup. The program includes three different components:
1. The self-help manual psycho-educational cognitive-behavioral based which includes information on different topics relevant for weight regain prevention, and tasks related to the different topic
2. The weekly feedback message system (FMS) with immediate feedback response which assesses risk behaviors, sending a feedback statement that relates to the information reported by the participant and his/hers historical reports, reinforcing and guiding when a problem is detected
3. Direct contact with a trained psychologist in the field through scheduled interactive chat sessions, where participants can pose personal questions.

Control Group (CGroup): Has only access to general information on obesity and bariatric surgery, and to the set of self-report measures at the different assessment times described below. CGroup participants will be informed about the assessment times and the possibility of accessing the full program after the study complete.

Both groups receive reminding messages in their email addresses every time a questionnaire/activity is available. Both groups will complete a similar set of questionnaires at baseline, every 4 month until the end of intervention, and at 6 and 12 month follow-up. Assessment includes anthropometric variables and psychological self-report measures.

Intervention type



Drug names

Primary outcome measures

1. Weight regain assessed at baseline, end of intervention and at follow up. Weight is measured in the presence of a research member with a TANITA scale.
2. Variant of weight loss estimations using percentage of total weight regain, percentage of excessive weight regain, percentage of total weight loss and percentage of excessive weight loss formulas.

Secondary outcome measures

1. Behavioral outcomes assessed weekly for one year during intervention as part of the monitoring feedback system of APOLO-Bari, using with a short self-report measure developed for this purpose: number of days with maladaptive eating behaviors (such as grazing, binge eating and overeating episodes), number of hours of sedentary and physical activities in the previous month
2, Psychological outcomes assessed with self-report measures at baseline (Tb), midterm (Tm4 and Tm8), end of treatment (Tf) and follow-up (Tfu6 and Tfu12) using the Eating disorder-15 questionnaire assessing eating disorder psychopathology, repetitive rating questionnaire to assess grazing, depression anxiety stress scale and negative urgency subscale to assess impulsivity.

Overall trial start date


Overall trial end date


Reason abandoned


Participant inclusion criteria

1. Aged between 18 and 65 years old
2. Underwent bariatric surgery more than 12 months before recruitment
3. Patients with significant post-operative weight loss (% excessive weight loss > 30%).

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Participants presenting significant weight regain (> than 15% of total weight loss) since nadir weight at the time of registration
2. No regular internet access
3. Inability to read and understand Portuguese instructions
4. Unwillingness to have/create and email account
5. Presence of active psychiatric disorder (e.g. bipolar disorder; psychotic disorder; suicidal ideation; eating disorders)
6. Intake of weight-affecting drugs
7. Concomitant weight loss treatment besides TAU
8. Pregnancy or lactation in female participants

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Hospital de Braga
Sete Fontes São Victor

Trial participating centre

Hospital de São João
Alameda Prof. Hernâni Monteiro

Sponsor information


University of Minho

Sponsor details

School of Life and Health Sciences
Campus Gualtar
+351 253 601700

Sponsor type




Funder type


Funder name

Foundation for Science and Technology

Alternative name(s)

Portuguese Science and Technology Foundation, Foundation for Science and Technology, FCT

Funding Body Type

government organisation

Funding Body Subtype

Federal/National Government



Results and Publications

Publication and dissemination plan

Participation in two annual scientific meetings will allow initial dissemination of the data. The first manuscript describing the study protocol is expected to be published in January 2016. A manuscript describing pilot data and characterizing the sample will be published in the end of December 2016. Midterm assessment will be analysed to describe trajectories of weight which are expected to be published in the beginning of 2017. Satisfaction and feasibility data will be published in 2019. End of treatment and follow/up data on efficacy will be published in 2020.

Intention to publish date


Participant level data

Available on request

Results - basic reporting

Publication summary

2016 protocol in:

Publication citations

Additional files

Editorial Notes

02/03/2016: Publication reference added.