Daily, about ten children are admitted for dental procedures under general anesthesia in the Faculty of Dentistry operating room between 7:00 am and 2:00 pm. The duration of surgeries vary, and the exact time children are brought to the recovery room is unknown. When the aroma diffuser is turned on in the recovery room, the plant's aroma remains until the end of the session, and it needs to be ventilated for the next aroma in the room. Therefore, it is possible to use one aroma each day, and all the children admitted will inhale the same aroma.
According to the limitations of the intervention, random allocation is done in a cluster manner.
Three identical bottles, one containing lavender, one containing rose, and one containing distilled water, are prepared. These bottles are named (A, B, C). Three closed envelopes are also prepared, each with one of A, B, or C written inside. The envelopes are numbered (1, 2, 3). On the first day of the trial, 1 hour before admission of the first patient, one of the numbers 1, 2, or 3 is selected using a random number generator, and the envelope is opened. Next, the contents of the corresponding bottle are poured into the diffuser. On the second day, using a random number generator, one of the numbers is selected, and the envelope is opened. On the third day, the remaining contents of the bottle are poured into the diffuser. On the fourth day, one of the three envelopes is chosen again. This process continues until the participants of all three groups reach 19 people.