European Journal of Human Genetics



Strengthening the reporting of genetic risk prediction studies (GRIPS): explanation and elaboration

A Cecile JW Janssens, John PA Ioannidis, Sara Bedrosian, Paolo Boffetta, Siobhan M Dolan, Nicole Dowling, Isabel Fortier, Andrew N Freedman, Jeremy M Grimshaw, Jeffrey Gulcher, Marta Gwinn, Mark A Hlatky, Holly Janes, Peter Kraft, Stephanie Melillo, Christopher J O'Donnell, Michael J Pencina, David Ransohoff, Sheri D Schully, Daniela Seminara, Deborah M Winn, Caroline F Wright, Cornelia M van Duijn, Julian Little and Muin J Khoury


Table 1. Reporting recommendations for evaluations of risk prediction models that include genetic variants

Title and abstract  
 1(a) Identify the article as a study of risk prediction using genetic factors. (b) Use recommended keywords in the abstract: genetic or genomic, risk, prediction.
Background and rationale2Explain the scientific background and rationale for the prediction study.
Objectives3Specify the study objectives and state the specific model(s) that is/are investigated. State if the study concerns the development of the model(s), a validation effort, or both.
Study design and setting4Specify the key elements of the study design and describe the setting, locations and relevant dates, including periods of recruitment, follow-up and data collection.a
Participants5Describe eligibility criteria for participants, and sources and methods of selection of participants.a
Variables: definition6Clearly define all participant characteristics, risk factors and outcomes. Clearly define genetic variants using a widely-used nomenclature system.a
Variables: assessment7(a) Describe sources of data and details of methods of assessment (measurement) for each variable. (b) Give a detailed description of genotyping and other laboratory methods.a
Variables: coding8(a) Describe how genetic variants were handled in the analyses. (b) Explain how other quantitative variables were handled in the analyses. If applicable, describe which groupings were chosen, and why.
Analysis: risk model construction9Specify the procedure and data used for the derivation of the risk model. Specify which candidate variables were initially examined or considered for inclusion in models. Include details of any variable selection procedures and other model-building issues. Specify the horizon of risk prediction (eg, 5-year risk).
Analysis: validation10Specify the procedure and data used for the validation of the risk model.
Analysis: missing data11Specify how missing data were handled.
Analysis: statistical methods12Specify all measures used for the evaluation of the risk model including, but not limited to, measures of model fit and predictive ability.
Analysis: other13Describe all subgroups, interactions and exploratory analyses that were examined.
Participants14Report the numbers of individuals at each stage of the study. Give reasons for non-participation at each stage. Report the number of participants not genotyped, and reasons why they were not genotyped.a
Descriptives: population15Report demographic and clinical characteristics of the study population, including risk factors used in the risk modeling.a
Descriptives: model estimates16Report unadjusted associations between the variables in the risk model(s) and the outcome. Report adjusted estimates and their precision from the full risk model(s) for each variable.
Risk distributions17Report distributions of predicted risks and/or risk scores.a
Assessment18Report measures of model fit and predictive ability, and any other performance measures, if pertinent.
Validation19Report any validation of the risk model(s).
Other analyses20Present results of any subgroup, interaction or exploratory analyses, whenever pertinent.
Limitations21Discuss limitations and assumptions of the study, particularly those concerning study design, selection of participants, measurements and analyses and discuss their impact on the results of the study.
Interpretation22Give an overall interpretation of results considering objectives, limitations, multiplicity of analyses, results from similar studies, and other relevant evidence.
Generalizability23Discuss the generalizability and, if pertinent, the health care relevance of the study results.
Supplementary information24State whether databases for the analyzed data, risk models and/or protocols are or will become publicly available and if so, how they can be accessed.
Funding25Give the source of funding and the role of the funders for the present study. State whether there are any conflicts of interest.

a Marked items should be reported for every population in the study.