Instrument Validation

This page presents the comprehensive psychometric validation of the 43-item TABS instrument (18 Barriers + 17 Readiness + 8 Maturity) using the full TABS dataset. All computations are produced by the open-source tabs_v2_unified_data_analysis.py script (Appendix N) and are fully reproducible.

Terms are linked to the Statistics Glossary. See also Factor Analysis for the hierarchical barrier factor structure.

1. Reliability

Five complementary reliability measures confirm strong internal consistency across all three TABS constructs. Every construct exceeds the .80 threshold for good reliability.

2. Exploratory Factor Analysis

EFA was conducted on each construct independently using Maximum Likelihood estimation with Promax oblique rotation. The number of factors was determined by Horn’s Parallel Analysis comparing actual eigenvalues against 95th-percentile random data eigenvalues.

Barriers extract 2 factors (Internal/Organizational + External/Compliance). Readiness and Maturity are each unidimensional. See Factor Analysis for the full loading matrix and hierarchical decomposition.

3. Confirmatory Factor Analysis

CFA tests whether the EFA-derived factor structure fits the data when specified as a confirmatory model. Single-factor models were fit for each construct, plus a 4-factor model for Barriers using the concept-mapping sub-constructs.

Barriers 4-Factor CFA (Concept-Mapping Sub-Constructs)

The 4-factor model (CFI = 0.887) improves over the single-factor model (CFI = 0.871) but remains below the .90 threshold, consistent with the EFA finding that 2 factors (not 4) best represent the data. Full CFA with cross-validation is planned at N=500.

4. Discriminant Validity

Discriminant validity assesses whether the three TABS constructs are empirically distinct from one another. Two complementary methods are used: HTMT and the Fornell-Larcker criterion.

HTMT Ratios

Fornell-Larcker Criterion

5. Construct Correlations

Barriers correlate negatively with both Readiness and Maturity, as expected: organizations with higher readiness and maturity perceive fewer barriers. Readiness and Maturity are positively correlated, reflecting overlapping organizational capability constructs.

6. Item Diagnostics

Flagged Items

Items are flagged if their corrected item-total correlation falls below .30, or if deleting them would increase Cronbach’s alpha. The current validation summary reports whether any items fall below the CITC threshold and the minimum observed CITC:

Inter-Item Correlation Summary

Optimal mean inter-item correlation: 0.15 to 0.50 (Clark & Watson, 1995). All three constructs fall within this range.

7. Bifactor Analyses

Bifactor models decompose each item's variance into a general factor and construct-specific factors. The omega-hierarchical (omega-h) statistic quantifies the reliability attributable to the general factor alone, while omega-total adds the construct-specific reliability. Explained Common Variance (ECV) reports the share of common variance accounted for by the general factor (Reise, Moore & Haviland, 2010). Both decompositions are fit with the DWLS estimator (proper for ordinal Likert data).

8. Assumption Checks

Multivariate normality and outlier diagnostics inform estimator choice. When multivariate normality is rejected (Mardia's skewness/kurtosis tests), the DWLS estimator is preferred over maximum-likelihood for confirmatory factor analysis on ordinal items. Mahalanobis squared distance flags multivariate outliers that may distort estimates if retained.

9. Validation Summary

The TABS instrument demonstrates strong reliability (all α > .85, all CR > .87) and adequate factor structure. Readiness and Maturity show excellent CFA fit as unidimensional scales. Barriers is inherently multi-dimensional (2-factor EFA), so single-factor CFA fit is expected to be poor. All HTMT ratios pass the conservative .85 threshold. Any item-level flags (CITC < .30) are retained for substantive reasons. AVE values below .50 are compensated by CR > .80 per Fornell & Larcker (1981) and are typical for broad, multi-faceted organizational behavior constructs.