The relationship between headache-attributed disability and lost productivity: 2. Empirical evidence from population-based studies in nine disparate countries

Table 4 Spearman correlations between disability¹ and lost paid worktime attributed to migraine by country (values of N vary because of zero values in some responses to either question)

Country	HALT question 1 (absenteeism)			HALT question 2 (presenteeism)			HALT questions 1 + 2 (total lost paid worktime)
Country	N	r_s	p	N	r_s	p	N	r_s	p
China	199	0.10	0.18	200	0.17	0.02	200	0.18	0.009
Ethiopia	479	−0.05	0.32	479	−0.08	0.09	479	−0.07	0.14
India	372	0.17	0.001	372	0.16	0.003	372	0.24	< 0.001
Lithuania + Luxembourg	509	0.15	< 0.001	502	0.20	< 0.001	523	0.20	< 0.001
Nepal	674	0.02	0.59	674	0.01	0.88	674	0.00	0.93
Pakistan	394	0.05	0.34	400	0.11	0.02	418	0.13	0.01
Russia	108	−0.02	0.83	108	0.10	0.29	108	0.09	0.38
Spain	339	0.21	< 0.001	343	0.30	< 0.001	354	0.30	< 0.001

HALT: Headache-Attributed Lost Time questionnaire. ¹ Calculated as proportion of time in ictal state*disability weight from GBD2015 [49]; significant p-values are emboldened.

ISSN: 1129-2377