# Understanding Sleep Health in Judo Referees: The Influence of Demographic and Athletic Factors
## 3 Results  
Tables 1 and 2 present demographic and professional characteristics of the study participants. Of the 73 referees included in the final analysis, 42 (57.5%) were male and 31 (42.5%) were female. In terms of educational attainment, 15 referees (20.5%) had completed high school, 5 (6.8%) held an associate degree, 42 (57.5%) held a bachelor's degree, and 11 (15.1%) had a postgraduate degree. Regarding referee qualification level, 31 participants (42.5%) were candidate referees, 21 (28.8%) were regional referees, 18 (24.7%) were national referees, and 3 (4.1%) held international (IJF) qualifications. The average refereeing experience was 6.6 years, with a 12.6-year athletic background. This study analysed 73 participants (42 males, 31 females) with a mean age of 29.79 \(\pm\) 11.0 years (range: 18-61). The mean refereeing experience of the participants was 6.58 \(\pm\) 8.12 years, and the mean sports history was 12.60 \(\pm\) 6.18 years. The Pittsburgh Sleep Quality Index (PSQI) was utilised to evaluate sleep quality, and the mean PSQI total score for male and female participants was 6.50 \(\pm\) 3.37 and 8.16 \(\pm\) 3.57, respectively. With regard to total sleep time, the mean sleep duration for males was 451 \(\pm\) 89.9 min, while for females it was 479 \(\pm\) 83.2 min. \begin{table}
\begin{tabular}{l l c c} \hline \hline  & **Variables** & **n** & **\%** \\ \hline \multirow{3}{*}{**Gender**} & Male & 42 & 57.5 \\  & Female & 31 & 42.5 \\  & High School & 15 & 20.5 \\  & Associate degree & 5 & 6.8 \\  & Bachelor’s & 42 & 57.5 \\  & Postgraduate degree & 11 & 15.1 \\  & Candidate & 31 & 42.5 \\
**Referee Qualification Level** & Region & 21 & 28.8 \\  & National & 18 & 24.7 \\  & International—IJF & 3 & 4.1 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: The descriptive data of the participants for gender, education level, and referee qualification level. Table 3 shows that an independent samples \(t\)-test revealed a statistically significant difference in sleep quality between genders: t(71) = \(-\)2.03, \(p\) = 0.046, d = 0.23 (small effect). [PERSON]'s d effect sizes were 0.43 for referees with good sleep quality (PSQI \(\leq\) 5) and 0.31 for those with poor sleep quality (PSQI \(>\) 5), indicating moderate and small-to-moderate standardised mean differences, respectively. Table 4 presents a Kruskal-Wallis H test to determine whether sleep quality (total PSQI score) differed by referee seniority/qualification level (1--Candidate, 2--Region, 3--National, 4--International/IJF). The test revealed no statistically significant difference in PSQI scores across the four groups of refereeing seniority: H(3, N = 73) = 5.09, \(p\) = 0.167. The results in Table 5 reveal that there was no statistically significant difference in PSQI total scores among education levels, F(3, 69) = 0.503, \(p\) = 0.682. The average score for high school graduates (N = 15) was 6.53 (SD = 3.27), the average score for associate degree graduates (N = 5) was 6.60 (SD = 2.97), the average score for undergraduate graduates \begin{table}
\begin{tabular}{c c c c c c} \hline  & **Referee Seniority/Qualification Level** & **n** & **Mean of Square** & **H** & \(p\) \\ \hline \multirow{4}{*}{**Total PSQI**} & 1—Candidate & 31 & 39.89 & 5.09 & 0.17 \\ \cline{2-6}  & 2—Region & 21 & 40.86 & & \\ \cline{1-1} \cline{2-6}  & 3—National & 18 & 27.31 & & \\ \cline{1-1} \cline{2-6}  & 4—International/IJF & 3 & 38.33 & & \\ \hline \end{tabular}  
* H: The Kruskal–Wallis H value.  
\end{table} 
Table 4: The Kruskal–Wallis H test comparing total PSQI scores across referee seniority levels.