Epidemiology and Biostatistics

The Epidemiology and Biostatistics unit provides collaboration, consultation and services on study design and data analysis.

Specific types of support include, but are not limited to:

Protocol development and review

Research question: Help with refining and turning research questions into research studies.

Study Design: Support in determining the most efficient and rigorous design for your study.

Sample Size Estimation: Assistance with determining the appropriate sample size in order to have sufficient power to detect a clinically important difference.

Randomization Schemes: We can generate random numbers and randomization schemes for your study.

Analysis Plan: It is important to have a clear statistical analysis plan for your data before the study is even conducted. We provide support for developing a suitable analysis plan for your protocol.

Protocol Review: We can review a completed protocol to evaluate the appropriateness of the design, analysis plan and sample size.


Data Cleaning: We perform the necessary checks, including identifying outliers and questionable observations, to ensure the accuracy of the data.

Statistical Analysis: We analyze your data using the appropriate statistical methods that will answer your research questions.

Publication development and review

Abstracts/Manuscripts: We provide assistance with the writing of the methods, results and discussion sections of abstracts and manuscripts. We also help with the presentation of the results using appropriate tables, graphs and figures.

General statistical advice

You can also contact us with all other research design and analysis questions.

Database Design and Data Management

The Database Design and Data Management team provides collaboration and consultation services on database design and data management to assist investigators and stakeholders at Johns Hopkins All Children’s Hospital and their collaborators.
The primary objective of the Database Design and Data Management team is to assist the study team in the design of data collection tools, design and build of the study database, query and report design and execution, and ongoing data management assistance throughout the life of the study.

The services of the team are matched to the needs of each study, and range from collaboration to routine service support to enhance the efforts of the study team. Specific types of support include, but are not limited to:

  • Data Dictionary Creation:Assistance with the layout of the study data fields and data collection tools, enforcing best practices and standards. Data validation will be implemented wherever applicable to ensure highest quality data input.

  • Database Build:Creation of the study database and corresponding web-based case report forms (CRFs) according to the IRB-approved protocol’s specifications regarding confidentiality and protected health information, with appropriate enforcement of data security through the implementation of user based accounts and permissions. The primary electronic data capture platform supported by the team is REDCap, a secure web application designed by Vanderbilt University specifically for data capture of research studies and operations. Qualtrics is also supported for direct electronic surveying, where needed.

  • Query and Report Builds:Creation and maintenance of any desired queries and/or reports, allowing the study team to regularly monitor data quality throughout the life of the study.

  • User Support and Training: User training at the outset of the study and support on a continuing basis, as needed. 

For more information, the Database Design team can be reached at [email protected].