Table 1 Number of questions, rating scale used in the 17 patient reported outcomes (PROs)

Visual Functioning index, VFI(Bernth-Petersen, 1981)

11

2 or 3

No

Difficulty, Severity^†

Activities of Daily Vision Scale,ADVS (Mangione et al. 1992)

22

5

No

Difficulty

Visual Activities Questionnaire,VAQ (Sloane et al. 1992)

33

5

Yes

Frequency

Cataract Symptom Score, CSS (Brenner et al., 1993; Curbow et al. 1993; Javitt et al., 1993)

5

4

Yes

Severity

Visual Function Index-14, VF-14(Steinberg at al., 1994)

14

5

Yes

Difficulty

Catquest (Lundstrom et al., 1997)

24

2^‡ or 4

No

Difficulty, Frequency,Severity

Visual Function and Quality ofLife, VF&QOL (Fletcheret al., 1997)

25

4

No

Difficulty, Global ratingof vision

Quality of Life and VisualFunction, QOLVFQ (Cartaat al., 1998 )

17

3

Yes

Difficulty

Visual Disability Assessment, VDA(Pesudovs and Coster, 1998)

18

4

Yes

Difficulty

Vision Core Measure 1, VCM1(Frost et al., 1998)

10

6

Yes

Frequency

Cataract Symptom Scale, CSScale(Crabtree et al., 1999)

15

5

No

Difficulty, Frequency

Impact of Cataract Surgery, ICS(Monestam and Wachtmeister, 1999)

4

4

No

Difficulty⁺

Technology of Patient Experiences,TyPE (Javitt et al., 1999)

13^*

5

No

Global rating of vision,Difficulty

Houston Vision Assessment Test,HVAT (Prager at al., 2000)

10

5^ξ

No

Difficulty, Severity

Impact of Vision Impairment, IVI(Hassell et al., 2000)

32

6

No

Difficulty/Severity, Frequency

National Eye Institute-VisualFunction Questionnaire,NEIVFQ (Mangione et al., 2000)

39^#

5, 6 or 11^{^}

No

Difficulty, Global ratingof health, Global ratingof vision, Frequency,Severity

Visual Symptoms and Quality ofLife, VSQ (Donovan et al., 2003)

26

8, 7, 5, 4, 3 or 2^$

No

Difficulty, Frequency,Global rating of vision