Description

For sample adults aged 18 and over who are not blind or for whom it was unknown if they are blind, VDIFSHELF rates a person's level of difficulty with finding something on a crowded shelf.

This variable is included in the Sample Adult Vision Supplement, sponsored by the National Eye Institute.

Comparability

Apart from a slight change in the universe and an introduction of a new category in the response format in the 2002 and 2008-forward surveys, VDIFSHELF is comparable over time. Please see the Universe tab for changes in universe between samples.

The changes in response categories allow for further detail as to why a person cannot perform an activity. In 1999, the response format was constructed on a five-point, ranging from "not at all difficult" to "can't do at all" (along with unknown responses). In the 2002 survey, a new category "do not do this activity" was added. In 2008, the categories "can't do at all" and "do not do this activity" were reworded to "can't do at all because of eyesight" and "do not do this activity for other reasons."

Universe

Availability

• 1999, 2002, 2008, 2016-2017

Weights

• 1999, 2002, 2008, 2016-2017 : SAMPWEIGHT