Statistical Support for CHPS Pilot Studies

CHPS offers statistical assistance through the Biostatistical Core for new pilot/preliminary proposals utilizing CHPS services. Such studies should be designed to collect pilot or preliminary data for future extramural funding applications. Faculty members and post-doctoral trainees with appropriate mentors who perform investigator-initiated studies in the CHPS are eligible for statistical support. The statistical assistance will be offered at no cost for qualified studies.

Pilot studies are the first step in the research process to provide information needed in planning and designing larger scale, hypotheses driven studies. For example, a pilot study can be used to assess feasibility of subjects’ recruitment, ability to measure and capture outcomes, to provide statistical estimation of parameters, and/or to demonstrate the ability to randomize subjects to interventions. Pilot studies usually involve a small sample size (≤ 30 participants). Sample size should be justified but not estimated to meet a specific statistical power.

Pilot studies do not:

  • Test specific hypotheses, but can generate data for hypotheses development.
  • Evaluate treatment safety, efficacy, and/or effectiveness.
  • Generate clinically important and meaningful effect sizes due to the small sample size used.

CHPS statistical support is limited to the studies that are planning to utilize or are currently utilizing at least one additional CHPS clinical Cores. (As an alternative resource for the studies requesting only statistical support, please contact the Biostatistics and Data Management Core (BDMC) at CHOP:

Statistical consultation in the study-planning phase can help address development of testable hypotheses, sample size estimation and justification, and the statistical analysis plan. Data management plays crucial role in streamlining future statistical analyses. If appropriate, consider requesting database development through the Bioinformatics Core to facilitate management of data at the start of the study.

Investigators requesting statistical consultation should complete and submit an Application for CHPS Statistical Consultation. The application should include a brief background, aims/hypotheses, description of study participants, data collection methods, the proposed primary outcomes and a preliminary analysis plan. The description must also include a paragraph on the planned use of CHPS resources.

As this initial biostatistical service is designed to provide consultation in the development of a research protocol to collect pilot or preliminary data, it is understood that the information provided will be preliminary in nature.

Once a pilot study that has received CHPS statistical consultation has been submitted for IRB approval, investigators can request support for data analysis along with the request to use other CHOPS Cores when the study is submitted to CHPS via eResearch. Once data collection is completed, the study investigator should submit an Application Form for CHPS Analytic Support for review.

Pilot/preliminary studies that are already using other CHPS cores and would like to add a request for analytic support can submit Application Form for CHPS Analytic Support for review. If approved, an eCHPS amendment will need to be submitted to request this service.

Once approved, investigators can schedule a meeting with the CHPS statistician to review the analysis plan in detail and set up a timeline of the analysis and manuscript submission. The plan should include authorship placement for the CHPS statistician, and authorship should be discussed prior to analyses for a qualified study.

Data analysis will be conducted when the following conditions are met:

  • recruitment completed,
  • final data locked for analysis,
  • a clear and finalized analysis plan,
  • authorship agreement, and
  • appropriate time line until manuscript submission.

Statistical services are considered general CHPS support, and PIs should acknowledge CHPS and the Clinical & Translational Science Award.

If you have questions or need more information about these services, please contact: John Krall, CHPS Administrative Director, 267-425-1790 or krallj [at]