internal validity


Also found in: Dictionary, Thesaurus, Legal, Encyclopedia, Wikipedia.

validity

 [vah-lid´ĭ-te]
the extent to which a measuring device measures what it intends or purports to measure.
construct validity the degree to which an instrument measures the characteristic being investigated; the extent to which the conceptual definitions match the operational definitions.
content validity verification that the method of measurement actually measures what it is expected to measure; see also face validity.
external validity the extent to which study findings can be generalized beyond the sample used in the study.
face validity a type of content validity, determining the suitability of a given instrument as a source of data on the subject under investigation, using common-sense criteria.
internal validity the extent to which the effects detected in a study are truly caused by the treatment or exposure in the study sample, rather than being due to other biasing effects of extraneous variables.
predictive validity the effectiveness of one set of test or research results as a predictor of the outcome of future experiments or tests.

internal validity

The extent to which differences between the intervention and control groups in a clinical study can be confidently attributed to the intervention and not to an alternative explanation, which requires reducing confounding factors and bias to a minimum. Explanatory clinical studies seek to maximise internal validity by rigorous control of all variables—e.g., age, sex, co-morbidities—other than the intervention itself.
References in periodicals archive ?
0 Internal validity Multiple-baseline A-B-C-B withdrawal design across design (baseline = transition periods functional analysis) 7.
Thus, considering that the sample randomization of this population was precluded, the option used obtained a sample large enough to ensure the internal validity of the results and with a high likelihood of representing PLHA undergoing treatment in the state of Paraiba because it is a small state, with high coverage by the Unified Health System (Sistema Unico de Saude--SUS), and most cases are treated in this referral hospital.
The study's internal validity was strengthened by using words from participant transcripts when describing research results.
Additional control over threats to internal validity can be introduced to the multiple-baseline design via two randomization schemes (Kratochwill & Levin, 2010).
It is worth re-emphasizing the fact that in all internal validity tables, Table 25 through Table 28, both Pearsons's and Spearman's correlations are calculated, and the values look to be relatively similar and significant.
These examples are presented to illustrate that oftentimes, practicing counselors will be compelled to find a balance between standards for internal validity that demonstrate a functional relationship between an intervention and an approach to measuring outcomes within those conditions that make sense clinically.
Control outcomes and exposures can improve the internal validity of nonexperimental studies because in certain situations they can detect confounding and selection bias via measurement of whether the treatment effect in the outcome of interest is confounded by unexpected factors (Brookhart et al.
Only variables with statistically significant differences were considered as predictor candidates--reliability reporting, threats to internal validity, threats to external validity, fading, and scaffolding intervention.
This brief look at two of the representative studies Schill and Kirk cite to empirically support claims of the dial meter's reliability and internal validity as a measurement tool yields mixed results.
7 The design controls for common threats to internal validity (e.
However, there has been a lamentable tendency of researchers to stress the strong internal validity of experiments and downplay the fact that they often have weak external validity.
Maslach and Jackson calculated the validity of micro tests that internal validity of questionnaire reported to Alpha Kronbach 71% to 90% and coefficient re test, 60% to 80% and internal validity is as following:, emotional exhaustion 90%, depersonalization 79% and personal capability 71% [12].

Medical browser ?