. 2021 Mar 3;8(3):188. doi: 10.3390/children8030188

Table 4.

Probability of having poor sleep quality in boys and girls by cities.

Sex	PSQI < 5 Points			PSQI ≥ 5 Points			p-Value	OR _{Seville vs. Reykjavik}	OR _{Seville vs. Tartu}	OR _{Tartu vs. Reykjavik}
Sex	Seville	Reykjavik	Tartu	Seville	Reykjavik	Tartu	p-Value	OR _{Seville vs. Reykjavik}	OR _{Seville vs. Tartu}	OR _{Tartu vs. Reykjavik}
Total	49%	59%	49%	51%	41%	51%	0.005 *	1.22 (1.07−1.40)	1.00 (0.93−1.07)	1.20 (1.05−1.37)
Boys	54%	62%	54%	46%	38%	46%	0.095	1.22 (1.00−1.50)	0.99 (0.90−1.11)	1.18 (0.99−1.40)
Girls	45%	55%	43%	55%	45%	57%	0.060	1.21 (1.01−1.45)	0.98 (0.89−1.08)	1.25 (1.01−1.54)

* Statistically significant differences at p < 0.05. PSQI = Pittsburgh Sleep Quality Index; PSQI < 5 points = good quality; PSQI ≥ 5 points = poor quality (high sleep latency, sleep disturbances and daytime dysfunction).