Key Issues

Realiability, Valillatly, Prescion and Accuarcy


The more presicse a measurement, the less likely to be unpredicitable. Precison is related to the refinement of the measuring process. An example of precison would be scoring a 180 in darts almost every time.

My First Video Recorded 180


this realtes to how close your measurment is to the 'golden standard' or what you are inteninanlly measuring. An example of this is would be a strikers scoring 8 out of 10 shots in the top right area of the net.

David Beckham's Incredible Accuracy

Internal Validity

The results of the study are related to the ideependent variable only. All other variables have been controlled.

External Validity

The results of the study can be used and applied to a real world situation.

Logical Validity

The dependent variable is tested using a related activity. E.G - Testing hand eye coordination using a throw and catch test.

Content Validity

Usually in an educational setting. The test at the end of the is related to the content of the course. E.G - At the end of a first aid course, the test is about first aid.

Construct Validity

A behavior that can be assumed following the results of a test. E.G - Scoring high on an IQ test, you would expect the student to be intellegent.

Criterion Validity


Running a test alongside a known to be true test, to see if your test is suitable. E.G - Maximal oxygen consumption test running alongside a stair climbing test to see if the stair climbing test will be valid.


Using a test result to predict how the subject will do in the future. E.G - If they got good results in GCSE's will predict they will get good results at A level.


The repeatability of a set of results.

There are 2 types of reliability; inter-researcher or test-retest reliabilty.

Research reliability can be one researcher conducting the same test on the same test on the same individual on a number of occasions and getting the same or similar results. An example of this is measuring someones heart rate at the same time of day for 4 weeks.

Errors can happen when:

- Researchers dont know what to do or how.

- The equipment might be broken.

- The wrong equipment being used.