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Application of meta-summary to derive a measurement instrument from the literature: a method exemplar.

BACKGROUND
Measurement tools are a common method to collect data in observational and survey research. Nurse researchers have developed numerous scales and instruments, many derived from published literature. However, few studies report systematic or replicable approaches to analysing the literature from which measures were derived. This is a significant challenge to construct validity.


AIM
To provide a method exemplar of meta-summary and categorical factor analysis to refine scale items and establish construct definition.


DISCUSSION
A rigorous method for deriving items from the literature is largely absent from nursing literature. This exemplar addresses the often-cited limitation of scales that authors rarely assure content validity before experts assess their newly derived scales.


CONCLUSION
Without sufficient methodological rigour, practitioners and researchers must speculate about the content validity of newly derived instruments. Meta-summary provides a useful approach to developing scales from the literature.


IMPLICATIONS FOR PRACTICE
The method detailed here is of use when deriving measurement instruments from the literature. It provides a systematic and replicable strategy that assures construct validity.