Results
pain
According to the inclusion criteria, 41 patients under treatment with HD were included in the study. None of the patients was excluded and left the treatment half-finished. The mean and standard deviation of age and HD treatment duration were 52.98 ± 14.10 and 3.8 ± 3.1 years, respectively. In addition, 25 patients (61%) in this study were male. The results showed a significant interaction between time and group (P = 0.007). In other words, there were carry-over effects. The period (P = 0.67) and sequence (P = 0.36) effects were not significant (Table 
The results of the linear mixed-effect model to assess group, carry over, period, and sequence effect on final pain with adjusted for baseline painDependent Variable: PainCooling spray group (A) first (Time 1) received cooling spray; then after 2 weeks (Time 2), the group received lidocaine spray; finally, after 2 weeks (Time 3), the group received placebo spray. Lidocaine spray group (B) first (Time 1) received lidocaine spray; then, after 2 weeks (Time 2), the group received placebo spray; finally, after 2 weeks (Time 3), the group received cooling spray. Placebo spray group (C) first (Time 1) received placebo spray; then, after 2 weeks (Time 2), the group received cooling spray; finally, after 2 weeks (Time 3), the group received lidocaine spray.As shown in Fig. 
The pain score according to periods and groups of the study