Table 3

Relative risk of blindness and MSVI nationally by age 1986, 1996 and 2019

Sample examinedBlindness (crude)MSVI (crude)
198619962019198619962019198619962019
Agennn%%%%%%
 30–39†807130322490.40.40.10.90.41.2
 40–4959084230961.00.20.31.92.12.7
 50–5940749617411.51.90.64.26.58.0
 60–6925536911543.93.51.28.612.118.0
 70+2262789489.77.57.119.928.137.6
Crude prevalence2.1
(1.5 to 2.6)
1.5
(1.1 to 2.0)
1.2
(0.9 to 1.4)
4.5
(3.6 to 5.3)
5.4
(4.7 to 6.2)
8.9
(8.3 to 9.5)
Age-standardised prevalence‡1.7
(1.2 to 2.1)
1.1
(0.9 to 1.3)
6.0
(5.2 to 6.8)
8.3
(7.9 to 8.8)
Risk ratio (compared with 1986)§0.8
(0.6 to 1.2)
0.5**
(0.3 to 0.7)
1.3*
(1.0 to 1.6)
1.9**
(1.6 to 2.3)
Risk difference (compared with 1986)¶−0.004
(−0.011 to 0.003)
−0.009
(−0.015 to −0.003)
0.135
(0.002 to 0.025)
0.387
(0.029 to 0.048)
Risk ratio (compared with 1996)§0.7* (0.5 to 1.0)1.5 (1.2 to 1.7)**
Risk difference (compared with 1996)¶−0.005
(−0.010 to −0.000)
0.252
(0.016 to 0.346)
  • NB 1996 and 1986 comparison data generated from unpublished survey data provided by H Faal.

  • *p<0.05 from χ2 test.

  • †35–39 in 2019.

  • ‡Age standardised to 1986 sample.

  • §Age-standardised prevalence risk ratio.

  • ¶Age-standardised prevalence risk difference.

  • **p<0.001 from χ2 test.

  • MSVI, moderate or severe vision impairment.