How to assess and take into account trend in single-case experimental design data

Area of Science:

• Behavioral Science
• Research Methodology
• Applied Psychology

Background:

• Trend is a critical data feature in single-case experimental designs (SCED).
• Applied researchers face challenges in assessing and managing baseline trends.
• Existing methods for trend analysis in SCED data require clarification and practical tools.

Purpose of the Study:

• To provide a comprehensive overview of trend assessment options in SCED data.
• To establish criteria for deciding when to control for baseline trend.
• To outline strategies for controlling baseline trend and address A-B comparison variations.
• To offer practical recommendations for applied researchers analyzing SCED data.

Main Methods:

• Review of multiple options for assessing trend presence in SCED data.
• Development of a criterion for determining the necessity of controlling for baseline trend.
• Exploration of strategies for controlling baseline trend.
• Introduction of a user-friendly website to implement trend line fitting and technique selection.

Main Results:

• Several options for trend assessment and control in SCED are reviewed with real data examples.
• Tentative recommendations are provided for each assessed question regarding trend analysis.
• A new website is available to assist researchers in fitting trend lines and selecting appropriate techniques.

Conclusions:

• The study provides practical guidance and tools for researchers analyzing SCED data with baseline trends.
• Recommendations aim to improve the rigor and clarity of trend-related data analysis in SCED.
• The developed website serves as a valuable resource for applied researchers.