The object of this study was to assess interobserver reliability in 23 tests concerning physical examination of the shoulder girdle. A physical therapist and a physical therapist/manual therapist independently performed a physical examination of the shoulder girdle in 91 patients with shoulder complaints of varying severity and duration. The observers assessed 23 items in total: active and passive abductions, passive external rotation, hand in neck (HIN) test, hand in back (HIB) test, impingement test according to Neer, springing test of the first rib and joint play test of the acromioclavicular joint. The interobserver reliability was evaluated by means of a Cohen's Kappa, the weighted Kappa and the intraclass correlation (ICC). Criteria for acceptable reliability were: Kappa value>or=0.60, ICC>or=0.75 or an absolute agreement>or=80%. The results showed that Kappa values varied from 0.09 (springing test first rib, stiffness) to 0.66 (springing test first rib, pain), weighted Kappa varied from 0.35 (pain during HIB) to 0.73 (range of motion HIB) and ICC varied from 0.54 (abduction passive starting point painful arc) to 0.96 (active and passive ranges of motion in abduction). In total 11 (48%) items fulfilled the criteria of acceptable reliability. In conclusion, there appears to be a great deal of variation in the reliability of the tests used in the physical examination of the shoulder girdle. Over 50% of the tests did not meet the statistical criteria for acceptable reliability.