Sampling and random allocation method
ADVERSE EFFECTS, BLIND

After approval was obtained from the Ethics Committee of Kermanshah University of Medical Sciences, four health centers in Kermanshah were designated for data collection. Eligible postmenopausal women were randomly assigned to Salvia officinalis (n = 32) and control (n = 32) groups and completed the baseline test questionnaires. Women were taught how to use aromatherapy. Each week, one of the researchers made phone calls to the participants to ensure proper use of the oil and to check for any adverse effects. After the six-week intervention, post-tests were conducted including the same questionnaires as in the baseline test to determine the effects of the intervention. In total, data was collected from two time points.
Permuted block randomization method was used in this research. The allocation sequence was determined by the computer using a table of random numbers with a block size of 6 and an allocation ratio of 1:1. Salvia officinalis and almond oils were stored in identical containers and coded by a pharmacist. To blind the allocation, a unique code was assigned to each woman and all codes were kept in an opaque envelope until the intervention. Neither the statistician (who performed the data analysis) nor the researcher (who participated in the sampling) was aware of group allocation.