Validity Validity of instrument is poor, it can have high reliability Reliability is poor, validity may also be poor. Cannot be validity without reliability Can be reliability without Whether the results truly represent what they are supposed to measure? Whether the results can be reproduced under the same conditions? Focuses on the outcome Achieving consistent results. Reliability vs Validity Reliability Validity Accuracy of a measure Consistency of a measure. Construct validity is the extent to which a study measures all of the constructs that it is supposed to measure.

Content validityĬontent validity is the extent to which a study covers all of the relevant content. If the weighing machine displays different weights each time, even though the patient whose weight is to be measured is the same, the weighing equipment is most likely malfunctioning and its results are not valid.įace validity is the extent to which a study appears to measure what it is supposed to measure. If a sensitivity questionnaire yields a trustworthy diagnosis when completed at multiple periods and with different physicians, it suggests that it has good validity as a physical illness measuring tool. In order for research to be valid, it must be free from error and bias. Validity is a term used in research to refer to the extent to which a study measures what it is supposed to measure. Without these measures, it would be difficult to know whether or not the results of a study are accurate. Internal consistency reliability is a measure of how well different items on a test correlate with each other.īoth test-retest and internal consistency reliability are important in research. Test-retest reliability is a measure of how well a test yields consistent results over time. Internal consistency Test-retest reliability.There are many types of reliability, but two of the most important Because the weighing equipment displays the same weight every time, the results are reliable. This suggests that the questionnaire’s reliability as a measure of the condition is low.Ī patient’s weight is measured numerous times under identical settings. Several physicians utilize the same questionnaire with the same patient but arrive at different conclusions. ExampleĪ sensitivity questionnaire is used by a physician to diagnose a patient with a long-term chronic condition. A reliable measure is one that produces similar results over time and across different circumstances.įor instance, if a researcher wants to study how well a new medication works, they would want to use a reliable measure of the medication’s effects. But what exactly is reliability? In short, reliability is the consistency of a measure. When it comes to research, reliability is key. How to ensure validity in your research? Reliability.How to ensure reliability in your research?.

Types of reliability and validity