Frequency-dependent female genital cutting behaviour confers evolutionary fitness benefits

Transcription

1 In the format provided by the authors and unedited. Frequency-dependent female genital cutting behaviour confers evolutionary fitness benefits Janet a. Howard* and Mhairi a. Gibson SUPPLEMENTARY INFORMATION VOLUME: 1 ARTICLE NUMBER: 0049 NATURE ECOLOGY & EVOLUTION DOI: /s

2 Supplementary Table 1 Single level logistic regression analysis examining predictors of a woman having daughter(s) with estimated by Odds Ratio (OR) and 95% confidence intervals (95% CI) Nigeria n 7,916 Burkina Faso n 10,360 Senegal n 6,941 Ivory Coast n 3,241 Mali n 7,792 OR (95% CI) p value OR (95% CI) p value OR (95% CI) p value OR (95% CI) p value OR (95% CI) p value Ethnic % (1.014, 1.023) (1.007, 1.023) (1.007, 1.018) (1.020, 1.044) (1.020, 1.028) Mother's status (47.61, 75.67) (9.260, 23.16) (55.48, ) (14.65, 39.96) (22.016, 37.51) Mother's religion (3.458, 4.720) (1.368, 1.767) (0.381, 1.786) (1.312, 2.085) (2,117, 3.235) Mother's education (0.550, 0.785) (0.447, 0.706) (0.463, 0.696) (0.349, 0.616) (0.739, 1.051) Mother's age (1.035, 1.052) (1.032, 1.047) (0.972, 0.989) (1.053, 1.077) (1.109, 1.128) Mother's wealth quintile Poorer (1.025, 1.664) (0.676, 0.941) (0.862, 1.266) (0.935, 1.704) (0.853, 1.215) Medium (0.769, 1.254) (0.582, 0.851) (0.744, 1.113) (0.950, 1.651) (0.791, 1.154) Richer (0.713, 1.167) (0.525, 0.737) (0.452, 0.787) (0.768, 1.405) (0.911, 1.248) Richest (0.499, 0.834) (0.207, 0.479) (0.197, 0.527) (0.470, 0.966) (1.133, 1.731) OR (95% CI) at increasing ethnic frequencies; 1% (1.014, 1.023) (1.007, 1.023) (1.007, 1.018) (1.020, 1.044) (1.020, 1.028) 50% (2.041, 3.171) (1.451, 3,094) (1.384, 2.340) (1.101, 8.491) (2.699, 3.928) 100% (4.162, 10.05) (2.105, 9.573) (1.914, 5.472) (6.937, 72.10) (7.286, 15.48) Reference category underlined; Mother s status: No, Mother s religion: Christian or other, Muslim Mother s education: No education, Some education Mother s wealth: Poorest, Poorer, Medium, Richer, Richest NATURE ECOLOGY & EVOLUTION DOI: /s

3 Supplementary Table 2 Multilevel logistic regression analysis examining predictors of a woman having daughter(s) with estimated by Odds Ratio (OR) and 95% confidence intervals (95% CI) Model 1 Model 2 Model 3 Parameter OR (95% CI)) OR (95% CI) OR (95% CI) Fixed effects Mother s status (No) Yes (24.85, 40.98) *** (24.85, 40.33) *** Mother s education (None) Some (primary or above) (0.695, 0.838) *** (0.694, 0.836) *** Mother s religion (Christian/other) Muslim (1.534, 1.906) *** (1.540, 1.900) *** Mother s wealth quintile (lowest) Second (0.877, 1.067) ns (0.876, 1.064) ns Third (0.798, 0.883) ** (0.757, 0.923) * Fourth (0.725, 0.808) *** (0.687, 0.847) *** Fifth (0.549, 0.695) *** (0.583, 0.658) *** Mother s age (years) (1.047, 1.058) *** (1.046, 1.057) *** Contextual factors Ethnic frequency (%) *** (1.015, 1.029) *** Random effects Ethnic group variation (3.684, ) *** (1.310, 2.181) *** (1.121, 1.445) *** Country variation (0.479, ) ns (0.651, ) ns (0.702, 19.69) ns Variance Analysis β (S.E.) β (S.E.) β (S.E.) Ethnic group level (Level 2) Variance (SE) (0.553) (0.131) (0.064) Explained variation (%) Reference ICC (%) MOR Country level (Level 3) Variance (SE) (0.097) (0.946) (0.848) Explained variation (%) Reference ICC (%) MOR * p<0.05 ** p <0.01 *** p < ns p>0.05 ICC - Intra-cluster correlation, MOR - median odds ratio Model 1: Null model without any exposure variable Model 2: Adjusted for individual variables (mother s status, education, age, religion and wealth) Model 3: Additionally adjusted for level 2 contextual variable, ethnic frequency (%) NATURE ECOLOGY & EVOLUTION DOI: /s

4 Supplementary Table 3 Pearson s correlation between ethnic Frequency (%) and the percentage difference in average number of surviving offspring for women aged in each ethnic group with compared to women without excluding women who have been infibulated COUNTRY Mali Ethnic Groups n 6 EXCLUDING INFIBULATED WOMEN Women n Pearson s R p value 1, Ivory Coast Nigeria 8 3, Burkina Faso 8 2, Senegal 7 1, NATURE ECOLOGY & EVOLUTION DOI: /s

5 Supplementary Table 4 Statistical comparison of adult height, and infant and child mortality between women aged years with and without. COUNTRY STATUS n Mali No 265 1,946 ADULT HEIGHT INFANT AND CHILD MORTALITY a) Mean height cm + 1d (SD, SE) (66.0, 4.06) (62.1, 1.41) T value Mortality at 1 month Mortality at 1-5 years ,807 Male children n % Female children n % 592 4, Male children n % 594 4, Female children n % 516 3,998 OR 1.32 (0.93, 1.86) OR 1.23 (0.83, 1.81) OR 1.06 (0.86, 1.31) OR 1.09 (0.87, 1.38) Ivory Coast No (58.4, 3.08) (61.0, 3.28) ,526 1, ,585 1, ,397 1, ,428 1,425 OR 1.10 (0.81, 1.51) OR 1.43 (1.01,1.96) * OR 1.21 (0.97, 1.51) OR 1.34 (1.06, 1.69) * Nigeria No Burkina Faso No 1,382 1, , (71.0, 1.19) (67.7, 1.65) (63.2, 4.96) (58.5, 1.67) ,547 4,284 * , ,401 4, ,160 3, ,913 3,778 OR 0.98 (0.81, 1.19) OR (0.81 (0.65, 1.01) OR 0.91 (0.80, 1.04) OR 0.90 (0.78, 1.03) , , ,486 OR 0.91 (0.64, 1.30) OR 1.23 (0.81, 1.87) OR 0.92 (0.74, 1.14) OR 1.14 (0.90, 1.43) Senegal No (64.3, 2.93) (68.1, 3.48) ***5.11 2,697 1, ,624 2, ,391 1, ,359 1,621 OR 1.37 (1.05, 1.78) * OR 1.42 (1.04, 1.96) * OR 1.52 (1.26, 1.82)*** OR 1.25 (1.03, 1.53) * *p<0.05, **p<0.01, ***p<0.001 a) Odds Ratios (OR) are shown here with 95% confidence intervals are the result of multivariate logistic analysis for the variables mother s status (reference; not cut) as a predictor of child mortality when controlling for wealth (quintiles) and education (no education/some education). NATURE ECOLOGY & EVOLUTION DOI: /s

6 Supplementary Table 5 Inclusion criteria for countries in West Africa COUNTRY CURRENT COUNTRY DHS SURVEY INCLUSION SUITABILITY POPULATION a PREVALENCE b DATE WOMEN n PREVALENCE NO. ETHNIC RANGE IN GROUPS c PREVALENCE NIGERIA 177.2m 27% ,385 46% % Suitable ALGERIA 38.8m - No DHS survey n/a GHANA 25.7m 4% ,691 9% % is the minority behavior in all ethnic groups, therefore not suitable. IVORY COAST 22.8m 38% ,060 44% % Suitable BURKINA FASO 18.4m 76% ,087 76% % Suitable. MALI 16.5m 89% ,583 87% % Suitable NIGER 17.5m 2% ,160 4% Not available Not available by ethnic group not available, therefore not suitable. SENEGAL 13.6m 26% ,688 40% % Suitable. GUINEA 11.5m 96% ,142 98% % is the majority behavior in all ethnic groups, therefore not suitable. BENIN 10.2m 13% ,599 12% % Only one ethnic group has over 50% and is small (n 532), therefore not suitable. TOGO 7.3m 4% ,480 9% 5 0 9% is the minority behavior in all ethnic groups, therefore not suitable. SIERRA LEONE 5.7m 88% ,658 90% % is the majority behavior in all ethnic groups, therefore not suitable. LIBERIA 4.1m 66% DHS survey does not include module n/a MAURITANIA 3.5m 69% DHS data not available n/a a b c Source: CIA World Fact Book July 2014 estimate Source: United Nations Children s Fund, Female Genital Mutilation/Cutting: A statistical overview and exploration of the dynamics of change, UNICEF, New York, This excludes non-nationals and smaller ethnic groups identified as other NATURE ECOLOGY & EVOLUTION DOI: /s

7 Supplementary Figure 1 Map of countries in West Africa included in the study Source: Google Maps Key: Countries shaded in grey are included in the study (Mali, Burkina Faso, Nigeria, Senegal and Ivory Coast) NATURE ECOLOGY & EVOLUTION DOI: /s

8 Supplementary Table 6 frequency by country and ethnic group SUPPLEMENTARY INFORMATION COUNTRY ETHNIC GROUP All Women aged years Women aged years status of daughters n % n % n % NIGERIA Tiv Kanuri/Beri Igala Fulani Ibibio Ijaw/Izon 1, Hausa 2, , Ekoi Igbo 4, , Yoruba 4, , TOTAL 14, , , MALI Sonrai 1, Tanachek Bobo M Dogon 1, Senoufo/Minianka 1, Peulh 1, , Sarkole/Soninke/Marka 1, , Malinke M 1, Bambara 3, , TOTAL 12, , , BURKINA FASO Toureg/Bella Gourounsi Gourmatche 1, Bobo BF Dagara Diola BF Mossi 8, , , Bissa Lobi Senoufo BF Fulfulde/Peul 1, TOTAL 15, , , SENEGAL Wolof 4, , Serer 1, Diola SN Poular 4, , Soninke SN Mandingue 1, TOTAL 12, , , IVORY COAST Bete Agni Baoule 1, Koulango Gouro Guere Yacouba Dioula IC Malinke IC Kayaka Senoufo IC 1, TOTAL 6, , , TOTAL 61, , , NATURE ECOLOGY & EVOLUTION DOI: /s