Table 2.

Proportion and the average annual change rate of functional limitations by education, age group, and sex, NHIS 2000–2014

	ADL			IADL			Physical function
	2000 %a	Change between 2000 and 2014 Percentage point	Annual change rate %	2000 %a	Change between 2000 and 2014 Percentage point	change rate %	2000 %a	Change between 2000 and 2014 Percentage point	Annual change rate %
All	5.0	0.9b	1.7**	12.6	−0.4	0.3	61.4	3.2c	2.0**
Education
Less than high school	7.3	3.9c	2.2**d	18.6	3.0b	0.4	68.7	5.6c	2.5**
High school	3.6	2.5c	2.6**d	9.8	2.7b	0.9*d	59.7	6.7c	2.1**
More than high school (reference)	4.3	−0.4	−0.1	10.5	−1.4	−0.3	56.3	3.8b	1.7**
Age group
65–74 years	3.1	0.3	1.5*	7.1	0.1	0.3	54.0	3.9b	2.0**d
75–84 years	5.8	0.5	1.5*	15	−1.7	0.1	66.2	2.2	1.7**d
≥85 years (reference)	11.8	4.3b	2.0*	33.3	−0.6	0.7	80.8	3.5	3.4**
Sex
Males	4.2	0.3	0.9	8.9	−0.3	−0.1	54.0	3.0b	2.0**
Females (reference)	5.6	1.4b	2.0**	15.3	−0.3	0.5	66.0	3.6c	2.1**

The analysis included 89 568 individuals aged 65 and above. The average annual change rate was estimated using a logistic model that adjusted for age group, sex, race, Hispanic origin, education and marital status. The annual change rate by subgroup was estimated by adding an interaction term between the trend variable and the characteristic of interest in the logistic model.

^*P < 0.05,

^**P < 0.001.

^aThe proportion was weighted using the NHIS sampling weights.

^bThe difference between 2000 and 2014 was statistically significant at P < 0.05.

^cThe difference between 2000 and 2014 was statistically significant at P < 0.001.

^dThe difference in the annual rate relative to that of the reference group was statistically significant at P < 0.05.