IRCT201011012560N4 IRCT 2010-12-02 Qom University of Medical Sciences and Health Services Comparing effects of two muscular injection methods on site-pain intensity of injection Comparing effects of two muscular injection methods on site-pain intensity of injection 2010-11-22 anticipated 75 Complete https://irct.ir/trial/2308 interventional Randomization: Randomized, Blinding: Not blinded, Placebo: Not used, Assignment: Parallel, Purpose: Supportive, Other design features: The sample size of the study was calculated with power of 80% and significance level of 5% according with the result of previous studies. N/A pain. Intervention 1: (1) In the first group, injections will perform with a plastic device, that consists of an oval disk (54 mm×40 mm) that supports multiple blunt pins (9 pins per cm2). In the middle of the oval support there is a hole of 5 mm of diameter. The use of the device is the following: first it is put on the skin at the injection site, then the injection needle is inserted in the hole of the device until it reaches the skin, without penetrating it; the device is then gently, but firmly, pressed onto the skin immediately prior and during the penetration of the injection needle into the skin. The device does not interfere with the needle penetration or with the drug delivery and there is no contact between the device and the injection needle. Intervention 2: (3) In the control group, a standard injection is give with no further intervention as it is routine in most hospitals. Intervention 3: (2) In the second group(cold therapy), the subjects will inform that a 2—3 cm piece of ice would be placed on the injection site on the gluteal muscle for 30 s prior to injection.