Pain in Solid and Clean Fuel Using Households

Table 3

Association of fuel types and fuel transitions with short-term trajectories of body pain sites from 2011 to 2018.

Variables	Model 1	Model 2	Model 3
	IRR (95% CI)	IRR (95% CI)	IRR (95% CI)
Fuel types
Cooking fuels
Clean fuels	Reference	Reference	Reference
Solid fuels	1.76 (1.60 to 1.93)	1.30 (1.21 to 1.39)	1.25 (1.16 to 1.34)
Time
2011	Reference	Reference	Reference
2015	1.35 (1.24 to 1.48)	2.54 (2.30 to 2.80)	2.54 (2.30 to 2.80)
2018	2.81 (2.60 to 3.05)	6.25 (5.78 to 6.75)	6.28 (5.81 to 6.78)
Interaction terms
fuels	0.88 (0.80 to 0.98)	1.02 (0.91 to 1.15)	1.02 (0.90 to 1.14)
fuels	0.70 (0.64 to 0.77)	0.79 (0.72 to 0.87)	0.78 (0.71 to 0.86)
Transition types
Fuel transitions
Always clean	Reference	Reference	Reference
Solid to clean	1.63 (1.45 to 1.82)	1.27 (1.17 to 1.38)	1.22 (1.13 to 1.33)
Clean to solid	1.53 (1.23 to 1.90)	1.28 (1.09 to 1.50)	1.24 (1.06 to 1.45)
Always solid	2.09 (1.88 to 2.33)	1.42 (1.31 to 1.53)	1.37 (1.26 to 1.48)
Time
2011	Reference	Reference	Reference
2015	1.35 (1.23 to 1.49)	2.51 (2.26 to 2.79)	2.50 (2.25 to 2.78)
2018	2.89 (2.65 to 3.15)	6.31 (5.81 to 6.85)	6.33 (5.83 to 6.88)
Interaction terms
to clean	0.89 (0.78 to 1.01)	0.98 (0.84 to 1.13)	0.98 (0.84 to 1.13)
to solid	1.00 (0.78 to 1.28)	1.07 (0.80 to 1.44)	1.09 (0.81 to 1.46)
solid	0.88 (0.78 to 0.99)	1.07 (0.93 to 1.23)	1.06 (0.93 to 1.22)
to clean	0.71 (0.63 to 0.79)	0.78 (0.69 to 0.88)	0.78 (0.69 to 0.87)
to solid	0.80 (0.64 to 1.01)	0.89 (0.70 to 1.12)	0.89 (0.70 to 1.13)
solid	0.67 (0.60 to 0.74)	0.77 (0.69 to 0.86)	0.76 (0.68 to 0.85)

, , . Abbreviations: IRR: incidence rate ratio; CI: confidence interval. Model 1 adjusted for age (continuous), gender (male or female), marital status (unmarried or married), residence (rural or urban), education level (less than lower secondary, upper secondary, and vocational training or tertiary), and currently working (yes or no). Model 2 additionally adjusted for smoking status (never or current/ever), alcohol consumption (never or current/ever), the number of diseases (0, 1, >1), and the number of pain sites at baseline (continuous). Model 3 further adjusted for household consumption expenditure (in quartiles), number of people living in the household (1, 2, >2), and heating fuels (clean fuels, solid fuels, or other fuels).