<prompt> Which one of the following will be affected by inter observer variation in epidemiological studies-SensitivityPredictive value of the positive testSpecificityReliability  <response>: ref: Park;s 23rd edition pg 138 Reliability repeatablility Precision: that is test must give consistent results when repeated more than once on the same individual or material, under same conditions. Reliability of a test depends on 3 major factors: Observer variation intra and inter Biological variation Errors relating to technical methods. 