Identifying　health　information　needs　is　an　important　part　of　user-centered　health　information　behavior　research.　Qualitative　information　behavior　studies　yield　deep　insights　but　have　limited　generalizability.　Quantitative　studies　using　questionnaire　instruments　offer　better　generalizability,　but　only　if　the　instruments　are　properly　developed　and　validated.　A　systematic　review　of　the　questionnaire　instruments　used　in　quantitative　studies　of　health　information　needs　was　carried　out,　focusing　on　whether　the　instruments　were　appropriately　developed　and　validated　(including　content　validity,　internal　consistency,　structural　validity,　construct　validity,　and　floor　and　ceiling　effects).　The　questionnaire　instruments　were　grouped　into　two　types:　those　that　assess　consumer　health　information　needs,　and　those　that　assess　patient　needs　that　impact　patient　quality　of　life　(including　health　information　needs).　One　hundred　and　seventeen　validation　studies　for　these　instruments　were　identified　in　the　literature　and　evaluated　for　their　methodological　quality　and　psychometric　properties.　It　was　found　that,　overall,　the　two　groups　of　questionnaire　instruments　were　not　well　developed:　only　structural　validity,　internal　consistency　tests　and　content　validity　analysis　were　performed　in　about　50　percent　of　them;　other　types　of　validations　were　missing　in　most　of　them.　Even　for　the　instruments　with　some　validation　tests　performed,　they　were　usually　not　designed　based　on　relevant　theory　to　support　content　validity,　lacked　specifications　for　handling　missing　data;　and　had　inappropriate　factor　analysis　in　the　structural　validity　test.　Instruments　used　for　assessing　patient　needs　were　found　to　perform　better　in　testing　construct　validity　and　evaluating　floor　and　ceiling　effects.　Practical　recommendations　include　the　use　of　information　needs　theories　and　the　results　of　qualitative　studies　to　inform　instrument　development,　as　well　as　the　advice　on　conducting　more　rigorous　validations.