Appendix I. Characteristics used to match the samples of ICs and controls. After matching the two groups were almost the same

Informal
caregivers
n=515 / Controls
n=2053
Age
Mean (SD) / 58.01 (16.12) / 57.66 (18.01)
Population of municipality.
> 10,000 inhabitants. / 127 (24.7%) / 484 (23.6%)
10,000 to 20,000 inhabitants. / 58 (11.3%) / 226 (11.0%
20,000 to 50,000 inhabitants. / 79 (15.3%) / 346 (16.9%)
50,000 to 100,000. / 70 (7.8%) / 188 (9.2%)
>100,000 to 500,000 inhabitants. / 47 (9.1%) / 196 (9.5%)
>500,000 inhabitants / 47 (9.1%) / 165 (8.0%)
Provincial capital / 117 (22.7%) / 448 (21.8%)
Sex.
Female / 325 (63.1%) / 1257 (61.2%)
Household composition.
Couple alone / 113 (21.9%) / 445 (21.7%)
Couple with children under 25 years old. / 75 (16.6%) / 304 (14.8%)
Couple with children over 25 years old. / 87 (16.9%) / 376 (18.3%)
Single parent with children under/over 25 years old / 101 (19.6%) / 382 (18.6%)
Couples, single parent with child under 25 years and others living in the household / 48 (9.3%) / 205 (10.0%)
Other type. / 91 (17.7%) / 341 (16.61%)
Educational Level.
Primary education or less / 207 (40.17%) / 827 (40.3%)
Secondary education / 213 (41.36%) / 871 (42.43%)
Professional certificate / 50 (9.71%) / 186 (9.06%)
College or equivalent / 45 (8.7%) / 169 (8.2%)
Monthly income of the entire household.
550 € or less / 14 (2.70%) / 77 (3.80%)
551-1050 € / 135 (26,21 / 557 (27.13%)
1051-1550 € / 129 (25.05%) / 471 (22.94%)
1551-2250 € / 79 (15.34%) / 309 (15.05%)
2251-2700 € / 19 (3.70%) / 68 (3.30%)
>2701 € / 25 (4.85%) / 107 (5.21%)
NA's / 114 (22.10%) / 464 (22.60%)
Social class, based on occupation of main household provider.
I / 26 (5.00%) / 132 (6.40%)
II / 32 (6.20%) / 124 (6.00%)
III / 98 (19.00%) / 352 (17.10%)
IV / 68 (13.20%) / 285 (13.90%)
V / 194 (37.70%) / 738 (35.90%)
VI - Workers/unskilled/not stated / 73 (14.20%) / 342 (16.70%)
NAs / 24 (4.70%) / 80 (3.90%)

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Appendix II.The overall mean difference of selected variables used to match ICs with control was reduced to almost 0 from the pre-matched sample to the final matched sample.

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