Table 1. Summary of the incidence and progression rates of trachomatous scarring.

Progression Factor	Sample Size	Follow-Up Interval	Rate	Setting	Prospective Design?	Associated Factors
Incident conjunctival scarring [28], [151]	367	5 y	20.4%	Tanzania	Yes	In children <10 y: active disease/persistent infection; female gender; age
Incident conjunctival scarring [24]	236 (age <7 y)	7 y	29.2% versus 9.6%	Tanzania	No	Higher rate was in children with severe-constant active disease; female gender; age
Worsening of conjunctival scarring [151]	85	5 y	47.1%	Tanzania	Yes	Not specified
Worsening of conjunctival scarring [25]	213a	14 y	68.5%	Tunisia	No	Active disease; household density
From conjunctival scarring to trichiasis [26]	523 (all women)	7 y	9.2%	Tanzania	No	Active disease; chlamydial infection; increasing age
From conjunctival scarring to trichiasis [152]	297	12 y	6.4%	Gambia	No	Mandinka ethnicity
From conjunctival scarring to trichiasis [27]	4,898	5 y	3.2%–15.1%	Tanzania	Nob	Increasing age
From minor to major trichiasis [153]	55	1 y	33%	Gambia	No	None mentioned
From minor to major trichiasis [27]	75	4 y	37%	Gambia	No	Conjunctival inflammation
From unilateral to bilateral trichiasis [153]	46	1 y	46%	Gambia	No	Baseline pannus; hot ash as an aid to epilation
From conjunctival scarring +/− trichiasis to corneal scarring [152]	302	12 y	6.0%	Gambia	No	Baseline trichiasis
From trichiasis to corneal scarring [27]	211	4 y	7.6%	Gambia	No	Increasing trichiasis severity; conjunctival inflammation
From trichiasis to corneal opacity [154]	4,898	10 y	27.2%–53.5%	Tanzania	Nob	Increasing age
Worsening of corneal scarring [153]	96	1 y	34%	Gambia	No	Conjunctival inflammation; bacterial growth

^aIncluding 82 people with no scarring at baseline.

^bEstimated incidence rates based on age-specific prevalence of scarring, trichiasis, and corneal opacity among women.