Article type
Abstract
Background
A tool for the evaluation of the internal validity of in vitro studies is needed to include the data as evidence in systematic reviews and chemical risk assessments.
Objectives
To systematically and transparently design and develop a tool for the evaluation of the internal validity of in vitro studies. The tool will be specifically applied to cell culture studies, including, but not restricted to, studies meeting the new approach methodology (NAM) definition. The tool is called INVITES-IN (IN VITro Experimental Studies INternal validity).
Methods
The development method is a uniquely rigorous approach grounded in four sub studies. First, we evaluated existing assessment tools combined with focus group discussions to identify how characteristics of the design or conduct of an in vitro study can affect its internal validity (item discovery). In the second study, group agreement on internal validity domains and items of importance for in vitro studies were identified via a modified Delphi methodology (item selection). In the third study, the draft version of the tool will be created, based on the data on relevance and importance of bias domains and items collected in Studies 1 and 2. In the fourth study, we will conduct user testing to evaluate the usability, accuracy, and consistency of application of the tool.
Results
To date we have created an item bank with 405 items that may be important for evaluating the internal validity of in vitro toxicology studies. These are now being prioritized during an ongoing Delphi process. By the fall we aim to have a draft tool we can present as well as preliminary results from user testing.
Conclusions
Adapting a transparent and systematic approach for developing a tool for the evaluation of the internal validity of in vitro studies has been a challenging process. However, we feel the methods we have used could be of relevance to other groups aiming to develop tools for including different types of studies in systematic reviews.
Relevance and importance to patients: Contribution to methods that result in more robust evidence production for systematic reviews of invitro studies.
A tool for the evaluation of the internal validity of in vitro studies is needed to include the data as evidence in systematic reviews and chemical risk assessments.
Objectives
To systematically and transparently design and develop a tool for the evaluation of the internal validity of in vitro studies. The tool will be specifically applied to cell culture studies, including, but not restricted to, studies meeting the new approach methodology (NAM) definition. The tool is called INVITES-IN (IN VITro Experimental Studies INternal validity).
Methods
The development method is a uniquely rigorous approach grounded in four sub studies. First, we evaluated existing assessment tools combined with focus group discussions to identify how characteristics of the design or conduct of an in vitro study can affect its internal validity (item discovery). In the second study, group agreement on internal validity domains and items of importance for in vitro studies were identified via a modified Delphi methodology (item selection). In the third study, the draft version of the tool will be created, based on the data on relevance and importance of bias domains and items collected in Studies 1 and 2. In the fourth study, we will conduct user testing to evaluate the usability, accuracy, and consistency of application of the tool.
Results
To date we have created an item bank with 405 items that may be important for evaluating the internal validity of in vitro toxicology studies. These are now being prioritized during an ongoing Delphi process. By the fall we aim to have a draft tool we can present as well as preliminary results from user testing.
Conclusions
Adapting a transparent and systematic approach for developing a tool for the evaluation of the internal validity of in vitro studies has been a challenging process. However, we feel the methods we have used could be of relevance to other groups aiming to develop tools for including different types of studies in systematic reviews.
Relevance and importance to patients: Contribution to methods that result in more robust evidence production for systematic reviews of invitro studies.