Independent t-tests for Pre and Post Scores by Group

Author

Joe

Published

July 15, 2025

Interactive Analysis Results

This interactive dashboard presents three types of analyses:

  1. Condition Analysis - Comparing pre and post scores between 20ms vs 100ms conditions
  2. CAP Risk Analysis - Comparing pre and post scores between High Risk vs Low Risk groups
  3. In-Lab vs. Online Analysis - Comparing pre and post scores between the in-lab 100ms and online 100ms groups.

Each analysis is available with three data filtering options:

  • All Data (no filtering)
  • Excluding Random Response (removing participants with elevated random response indexes)
  • Excluding All Invalid Responses (removing participants with all elevated validity indexes)

Condition Comparison: 20ms vs 100ms (in lab) vs 100ms (online)

This table compares pre and post scores between the 20ms and 100ms conditions across all measured variables.

Overall Sample Sizes

Condition 1 ( 100ms ): 23

Condition 2 ( online100ms ): 98

Condition 3 ( 20ms ): 24

Sample Sizes by Variable

Number of non-missing observations for each variable and time point:

Descriptive Statistics

Paired T-tests Within 100ms Condition

Pre vs Post comparison for 100ms condition

Paired T-tests Within online100ms Condition

Pre vs Post comparison for online100ms condition

Paired T-tests Within 20ms Condition

Pre vs Post comparison for 20ms condition

Condition Comparison: 20ms vs 100ms (Excluding Random Response)

This table compares pre and post scores between the 20ms and 100ms conditions across all measured variables, excluding participants with elevated random response indexes.

Overall Sample Sizes

Condition 1 ( 100ms ): 23

Condition 2 ( online100ms ): 93

Condition 3 ( 20ms ): 23

Sample Sizes by Variable

Number of non-missing observations for each variable and time point:

Descriptive Statistics

Paired T-tests Within 100ms Condition (Excluding Random Response)

Pre vs Post comparison for 100ms condition

Paired T-tests Within online100ms Condition (Excluding Random Response)

Pre vs Post comparison for online100ms condition

Paired T-tests Within 20ms Condition (Excluding Random Response)

Pre vs Post comparison for 20ms condition

Condition Comparison: 20ms vs 100ms (Excluding All Invalid Responses)

This table compares pre and post scores between the 20ms and 100ms conditions across all measured variables, excluding participants with elevated random response, faking good, and faking bad indexes.

Overall Sample Sizes

Condition 1 ( 100ms ): 17

Condition 2 ( online100ms ): 66

Condition 3 ( 20ms ): 11

Sample Sizes by Variable

Number of non-missing observations for each variable and time point:

Descriptive Statistics

Paired T-tests Within 100ms Condition (Excluding All Invalid Responses)

Pre vs Post comparison for 100ms condition

Paired T-tests Within online100ms Condition (Excluding All Invalid Responses)

Pre vs Post comparison for online100ms condition

Paired T-tests Within 20ms Condition (Excluding All Invalid Responses)

Pre vs Post comparison for 20ms condition

CAP Risk Analysis: All Data

This analysis examines differences between High Risk and Low Risk groups based on CAP Inventory results using all available data.

Sample Sizes

Total participants: 111

Group 1 ( High Risk ): 51

Group 2 ( Low Risk ): 60

Overall Pre-Post Comparisons

Paired t-tests comparing pre and post scores across all participants, regardless of risk group.

Group Comparisons

Independent t-tests comparing High Risk vs Low Risk at both pre and post time points.

Descriptive Statistics by Risk Group
Independent t-test Results

CAP Risk Analysis: Excluding Random Response

This analysis examines differences between High Risk and Low Risk groups based on CAP Inventory results, excluding participants with elevated random response indexes.

Sample Sizes

Total participants: 107

Group 1 ( High Risk ): 47

Group 2 ( Low Risk ): 60

Overall Pre-Post Comparisons

Paired t-tests comparing pre and post scores across all participants, regardless of risk group.

Group Comparisons

Independent t-tests comparing High Risk vs Low Risk at both pre and post time points.

Descriptive Statistics by Risk Group
Independent t-test Results

CAP Risk Analysis: Excluding All Invalid Responses

This analysis examines differences between High Risk and Low Risk groups based on CAP Inventory results, excluding participants with random response, faking good, and faking bad indexes.

Sample Sizes

Total participants: 75

Group 1 ( High Risk ): 38

Group 2 ( Low Risk ): 37

Overall Pre-Post Comparisons

Paired t-tests comparing pre and post scores across all participants, regardless of risk group.

Group Comparisons

Independent t-tests comparing High Risk vs Low Risk at both pre and post time points.

Descriptive Statistics by Risk Group
Independent t-test Results

In-Lab vs. Online Comparison: All Data

This analysis compares the in-lab 100ms group with the online 100ms group using all available data.

Sample Sizes

Total participants: 121

Group 1 ( 100ms ): 23

Group 2 ( online100ms ): 98

Group Comparisons

Independent t-tests comparing 100ms vs online100ms at both pre and post time points.

Descriptive Statistics by Group
Independent t-test Results

In-Lab vs. Online Comparison: Excluding Random Response

This analysis compares the in-lab 100ms group with the online 100ms group, excluding participants with elevated random response indexes.

Sample Sizes

Total participants: 116

Group 1 ( 100ms ): 23

Group 2 ( online100ms ): 93

Group Comparisons

Independent t-tests comparing 100ms vs online100ms at both pre and post time points.

Descriptive Statistics by Group
Independent t-test Results

In-Lab vs. Online Comparison: Excluding All Invalid Responses

This analysis compares the in-lab 100ms group with the online 100ms group, excluding participants with any elevated validity indexes.

Sample Sizes

Total participants: 83

Group 1 ( 100ms ): 17

Group 2 ( online100ms ): 66

Group Comparisons

Independent t-tests comparing 100ms vs online100ms at both pre and post time points.

Descriptive Statistics by Group
Independent t-test Results

Methods

This analysis examines three key comparisons:

  1. Condition Analysis: Comparing pre and post scores between 20ms and 100ms conditions.

  2. CAP Risk Analysis: Comparing pre and post scores between High Risk and Low Risk groups.

  3. In-Lab vs. Online Analysis: Comparing pre and post scores between the in-lab 100ms group and the online100ms group