Skip to main content

Table 1 Criteria for good measurement properties

From: Psychometric properties of medication adherence instruments in cardiovascular diseases and type 2 diabetes mellitus: systematic review protocol

Measurement property

Rating

Criteria

Structural validity

+ 

CTT:

CFA: CFI or TLI or comparable measure > 0.95 OR RMSEA < 0.06 OR SRMR < 0.08

IRT/Rasch:

No violation of unidimensionality: CFI or TLI or comparable measure > 0.95 OR RMSEA < 0.06

OR SRMR < 0.08

AND

no violation of local independence: residual correlations among the items after controlling for the dominant factor < 0.20 OR Q3's < 0.37

AND

no violation of monotonicity: adequate looking graphs OR item scalability > 0.30

AND

adequate model fit

IRT: χ2 > 0.001

Rasch: infit and outfit mean squares ≥ 0.5 and ≤ 1.5 OR Z-standardized values >  − 2 and < 2

?

CTT: not all information for ' + ' reported

IRT/Rasch: model fit not reported

-

Criteria for ' + ' not met

Internal consistency

+ 

At least low evidence for sufficient structural validity AND Cronbach's alpha(s) ≥ 0.70 for each

unidimensional scale or subscale

?

Criteria for “At least low evidence for sufficient structural validity” not met

-

At least low evidence for sufficient structural validity AND Cronbach's alpha(s) < 0.70 for each

unidimensional scale or subscale

Reliability

+ 

ICC or weighted Kappa ≥ 0.70

?

ICC or weighted Kappa not reported

-

ICC or weighted Kappa < 0.70

Measurement error

+ 

SDC or LoA < MIC

 

?

MIC not defined

 

-

SDC or LoA > MIC

Hypotheses testing for construct validity

+ 

The result is in accordance with the hypothesis

 

?

No hypothesis defined (by the review team)

 

-

The result is not in accordance with the hypothesis

Cross-cultural validity\measurement invariance

+ 

No important differences found between group factors (such as age, gender, language) in multiple

group factor analysis OR no important DIF for group factors (McFadden's R2 < 0.02)

?

No multiple group factor analysis OR DIF analysis performed

-

Important differences between group factors OR DIF was found

Criterion validity

+ 

Correlation with gold standard ≥ 0.70 OR AUC ≥ 0.70

?

Not all information for ' + ' reported

-

Correlation with gold standard < 0.70 OR AUC < 0.70

Responsiveness

+ 

The result is in accordance with the hypothesis OR AUC ≥ 0.70

?

No hypothesis defined (by the review team)

-

The result is not in accordance with the hypothesis OR AUC < 0.70

  1. Source: Extracted from Prinsen et al., 2018, p. 1152
  2. Note: AUC = area under the curve; CFA = confirmatory factor analysis; CFI = comparative fit index; CTT = classical test theory; DIF = differential item functioning; ICC = intraclass correlation coefficient; IRT = item response theory; LoA = limits of agreement; MIC = minimal important change; RMSEA = root mean square error of approximation; SEM = standard error of measurement; SDC = smallest detectable change; SRMR = standardized root mean residuals; TLI = Tucker–Lewis index; “ + ” = sufficient; “ − ” = insufficient; “?” = indeterminate