An observational study in Experts in Physical Activity Prescription and Risk Health Screening, sponsored by Polytechnic Institute of Porto. Active, not recruiting at 1 site in Portugal. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-25.
Sponsored by Polytechnic Institute of Porto · Observational
This study aims to validate a personalized physical activity algorithm for risk screening and individualized exercise prescription using a modified online Delphi process. International experts in physical activity and exercise will evaluate the algorithm's components over two rounds of questionnaires, with consensus defined as ≥70% agreement. If needed, a focus group will resolve any remaining disagreements. Validation of this algorithm may support safer, more effective autonomous exercise, promoting adherence, improved health outcomes, and population-level benefits.
Study Phases - eDelphi Validation of the APPA Algorithm
Phase 1 - Round 1 (Initial Online Questionnaire):
The first phase consists of an online survey in which international experts in physical activity and exercise will evaluate the components of the personalized physical activity algorithm for health risk screening and individualized exercise prescription. Experts will assess the relevance, clarity, and clinical appropriateness of each item. Feedback from this round will identify items requiring modification or clarification.
Phase 2 - Round 2 (Re-evaluation):
The second phase consists of a consecutive online survey round, in which experts will re-evaluate the revised algorithm components based on feedback from Round 1. Experts will have the opportunity to adjust their ratings. This phase aims to move items closer to consensus (≥70% agreement).
Phase 3 - Optional Focus Group (if needed):
If consensus is not reached on specific items after Round 2, an online focus group will be conducted to discuss and resolve remaining disagreements. This discussion will help refine the algorithm and ensure agreement on all components.
9,798 studies on the registry are indexed under Motor Activity; 1,910 are open to participants now.
This study's planned enrollment of 9 is below the median of 98 across 1,235 observational studies indexed under Motor Activity.
Browse Motor Activity studies →Polytechnic Institute of Porto is the lead sponsor of 14 studies on the registry; 6 are open to participants now.
Counted across the registry records on this site, refreshed daily.
The study population will consist of international experts in the field of Physical Activity and Exercise. Participants will be identified based on their recognized scientific or professional experience and possession of a relevant doctoral degree. Recruitment will be primarily via institutional email invitations, supplemented by personal contacts when needed. Eligible experts will voluntarily participate in two rounds of an online modified Delphi questionnaire and, if required, an online focus group to resolve any remaining disagreements. The targeted panel size is 9 - 18 experts to ensure representativeness and methodological robustness.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cohort of experts in physical activity and exercise with recognized scientific or professional experience and a relevant doctoral degree. Experts will validate a digital algorithm for health risk screening and individualized physical activity prescription via a modified online Delphi process. Two rounds of anonymous questionnaires will assess the relevance, clarity, and clinical appropriateness of algorithm components. If consensus (≥70% agreement) is not reached, a follow-up online focus group will resolve disagreements. Recruitment will be through institutional emails and professional networks. Participation is voluntary, with informed consent obtained. Panel size: 9-18 experts, consistent with Delphi methodology to ensure representativeness and robustness.
Expert consensus on algorithm components
Consensus defined as ≥70% agreement among experts using a 9-point Likert scale in a two-round modified Delphi process evaluating the relevance and clarity of algorithm items.
Time frame: Up to 2 months
Plan to share: No
No publications or documents are linked to this record.
Ran from Mar 2026 to primary completion in Jun 2026, 3 months.
Of 490 non-industry observational studies under Motor Activity, half reached primary completion within 22 months of starting (the median), counting those still running; a quarter within 8 and three quarters within 48. This study's 3 months is below that.
Counting every sponsor, half of 500 studies reached it within 22 months; a quarter within 8 and three quarters within 48.
Primary completion moved once since we started tracking on Sep 25, 2026: May 2026 → Jun 2026, on Sep 25, 2026.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is active, not recruiting, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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Polytechnic Institute of Porto