|Year : 2018 | Volume
| Issue : 1 | Page : 1-2
N Gopi Chander
Professor, Department of Prosthodontics, SRM Dental College, SRM University, Chennai, Tamil Nadu, India
|Date of Web Publication||17-Jan-2018|
Dr. N Gopi Chander
496, 3rd Main Road, TNHB Colony, Velachery, Chennai - 600 042, Tamil Nadu
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Chander N G. Study validity. J Indian Prosthodont Soc 2018;18:1-2
The country on average produces 500 prosthodontic research studies annually. Lesser studies among these are getting translated into progressive research. These findings are unable to translate to advanced stage due to major limitations in the study design, methodology, motivation, interest, and funding. The study design, instrumentation used, and data collection make the inferences obtained from these studies less valid. The validity of the study design is essential for both in terms of internal acceptance for standardization and in terms of external recognition for universal acceptance.
The name valid is derived from the Latin word validus indicating strong. This implies that the design and methodology followed should be strong and accepted globally. Validity in the study design denotes that the accuracy, trustworthiness of instruments used, and data or findings collected are highly ordered and obtained with a reduced systemic error. When the validity is within acceptable limits, it aids in wider acceptance and it leads to progressive research.
The validity is of two types: internal validity and external validity. The internal validity is the steps taken or standards followed by the researchers in the study environment to obtain the truthful results. The external validity is the generalization followed for wider acceptance of global population. Although these validation procedures are essential for the clinical studies, greater care is necessary for in vitro studies for the progressive research.
Numerous factors affect the validity of the study. The internal validity is affected by the size of the subject/specimen, type or variability of the subject, attrition of the samples, maturation, time taken for evaluation, history, and instrument or assessment sensitivity. The external validity is controlled by population representation, time/duration of evaluation, research environment, researcher characteristics, data collection, interaction of the subject to research, and control of independent variables. It is essential that these factors are understood in study design and controlled for robust study design and acceptance.
The study validity can be evaluated by translation or criteria. It can also be measured by content, face, predictable, creative, concurrent, convergent and divergent, or dissimilar measures of validity. The validity in the study can be improved by defining the aim and objective of the study, synchronizing the assessment measures to the objectives. In addition, it is advisable to compare with the outside environment or external measure for wider acceptance.
The structure of the study design can have different levels of validity. The randomized clinical trial has higher internal validity than cohort, case-control, or cross-sectional studies. The observational studies have higher external validity compared to interventional studies. Adequate measure should be followed to avoid the issues, and it has to be optimized to obtain the essential validity in the study. The adaptation of appropriate study protocols such as CONSORT and STROBE aids in obtaining essential standardization.In vitro studies following the regular guidelines listed by the ISO, ADA, and BIS can establish higher norms and acceptance.
Adherence to the study design, protocol, and following the validity measures aids in better appreciation of the studies and can enhance the translatory research to an advanced stage.
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Chander NG. Standardization of in vitro
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