Acceptability & Feasibility 
Several studies have documented the acceptability and feasibility of Health LiTT.
English and Spanish:  
Patients in primary care clinics and clients at community organizations (n=97 English; n=134 Spanish) (Yost et al.,2009):
  • cognitive interviews conducted with a subset:
  • the majority were comfortable answering the questions
  • the majority correctly described the steps needed to answer each type of question (prose, document, quantitative):

Comments  the majority reported that the touchscreen was easy to use
"The instructions are clear; you read the question and choose the correct answer to complete the sentence." 
"Look at entire chart, look at question, then back at chart and choose answer." 
"I read the question and looked at choices below; I used math skills."
The words were big so I didn’t have to put glasses on. The screen was nice and bright. 
I like the headphones and it allowed me to concentrate better. 
It was fun.

Primary care patients (n=610) in clinics for underserved populations (Yost et al., 2010):
  •   completed Health LiTT on a tablet touchscreen in the clinic waiting room
  •  the majority (93%) had no difficulty using the touchscreen, including those who were computer-naïve (87%)
  •  average length of time to complete 30 items was 18 minutes
  •  the majority (75%) rated their study participation experience “better than expected”
It was interesting and challenging to me because I have never used a computer easy. But it was easy. 
It was exciting to use because I felt that I learned something new. Being my first time using the computer, it was enjoyable. 
It was easy; you can answer the questions at your own pace.
Validity is defined as the degree to which an instrument measures what it was designed to measure. (Aronson, et al., 2002 )
Evidence for several different types of validity for Health LiTT.
Content Validity see (Yost et al., 2009) :
  • English and Spanish Item Development and Translation Advisory Panels provided input on item content, difficulty and quality.
  • Only one concept is clearly articulated for each item.
  • Content information is accurate.T
  • Topics were selected based on interest and importance to both clinicians and patients.
    Item content is expected to be fairly fixed (i.e., not likely to change due to advances in medicine or technology).
Construct Validity (Yost et al.,2010; Hahn et al., 2011): 
  • lower health literacy for those with lower education or lower income
Criterion Validity (Yost et al., 2011):
  •  Associated with TOFHLA categories (inadequate, marginal, adequate)
  • The importance of health literacy has grown considerably among researchers, clinicians, patients and policymakers. Better instruments and measurement strategies are needed. 
  • Health LiTT meets psychometric standards (reliability of 0.90 or higher) for measurement of individual respondents in the low to middle range (Hahn, 2011)  Better measurement precision will enhance the ability to estimate the size of the population at risk from low health literacy, and to identify vulnerable patients in clinical settings.  
  • The Health LiTT measurement system provides a useful strategy for those who may want to explore health literacy screening in clinical practice.
  • Health LiTT is incorporated into Assessment CenterSM which is a free, online research management tool (   
  • Assessment CenterSM enables customization of items and instruments, real-time scoring of CATs, secure storage of protected health information, automated accrual reports, real-time data export, and many other features.  
  • Use of Assessment CenterSM for Health LiTT will enable administration of Health LiTT on the same touchscreen used for other patient-reported outcomes, thus providing a feasible way to assess patients’ literacy in clinical practice and research.
Scoring & Reports
  • Item responses are scored using an IRT algorithm. See IRT definition in FAQs 
  • Health LiTT uses a T-score (mean=50, SD=10). 
  • The Health LiTT score meets psychometric standards (reliability of 0.90 or higher) for measurement of individual respondents in the low to middle range (Hahn et al., 2011) .
  • Reports (coming soon)
  • Health LiTT uses a T-score (mean=50, SD=10). 
  • A T-score of 50 corresponds to the mean score of the primary care development sample which involved 608 patients being treated in clinics for underserved populations (Hahn et al., 2011)
  • A score of 50 was reported for a group of older adults (age 55-74) (Yost et al., 2011) with marginal health literacy on the Test of Functional Health Literacy in Adults (TOFHLA; Parker et al., 1995).
T-scores and raw scores (proportion correct) are summarized below for a 14-item short form administered in a recently completed study of people with type 2 diabetes
English (n=146)
Spanish (n=149)
Health LiTT T-score, mean (SD)
52.1 (10.6)
47.8 (8.9)
Health LiTT raw score, mean (SD)
8.5 (3.1)
7.3 (2.9)