Table 2.

Diagnostic criteria used for convergence insufficiency.

Dysfunction	Study	Diagnostic criteria
		Symptoms	Clinical signs
			Phoria	PFV	NPC	AC/A	BAF	MEM	PRA	VF	FD curve
				NFV					NRA
Convergence insufficiency	2006, Marran LFa 37	CISS V-15 symptom questionnaire	Exophoria at near ≥4 Δ greater than at distance Von Graefe method	PFV failures to reach Sheard's 11criteria or failure to have minimum normative PFV at near, ≤15Δ for break	≥6 cm break
	2004, Rouse MW39	CISS V-15 symptom questionnaire score ≥ 21	Exophoria at near ≥4 Δ greater than at distance Von Graefe method	PFV failures to reach Sheard's 11criteria or failure to have minimum normative PFV at near, ≤15Δ for break	≥6 cm
	2003, Borsting EJ40	CISS V-15 symptom questionnaire score ≥ 16	Exophoria at near ≥4 Δ greater than at distance Von Graefe method	PFV failures to reach Sheard's 11criteria or failure to have minimum normative PFV at near, ≤15Δ for break	≥6 cm
	2002, García,Ab 41	Reported without questionnaire	Exophoria at near >6 Δ. Cover test method	PFV ≤ 11/14/3 Δ, at least one of three responses of blur/break/recovery	>10 cm break or >17.5 recovery	Calculated AC/A < 3/1	≤3 cpm Difficulty clearing +2 D (±2 D)	<+0.25 D	NRA ≤1.50 D
	1999, Borsting E28	CIRS symptom questionnaire score ≥9	Exophoria at near ≥4 Δ greater than at distance Method not specified	Failed Sheard's criterion or minimum PFV at near, ≤12/15/4 Δ	≥7.5 cm break
	1991, Dwyer PS4	Not reported	Exophoria at near = 12 Δ	PFV = 0 blur/break and recovery		≤3/1				Diplopia with 12 Δ Base-out	Type 3 curve
	1986, Daum KM44	Reported without questionnaire	If the angle at far is ≤5 Δ exophoria, it must be at near at least 4 Δ more exo If the angle at far is ≥6 exophoria, it must be at near at least 10 Δ more exo Cover test method

NPC: near point of convergence, NFV/PFV: negative/positive fusional vergence, BAF: binocular accommodative facility, MEM: MEM dynamic retinoscopy, PRA/NRA: positive/negative relative accommodation, Δ: prism diopters.

^aAuthors consider having an exophoria at near a fundamental sign and CI may be diagnosed with one, two or three clinical signs.

^bAuthors diagnose CI considering exophoria, PFV and NPC as fundamental signs and patients must have at least two signs of the remaining four signs.