Abstract

Numeracy skill level of patients has great influence on their preferences and priorities for the treatment options concerning their healthcare. The elicitation of patient preferences in healthcare, along with the increasing degree of patients’ participation in their own treatment decision- making immensely signify the importance of the topic. Numeracy in healthcare domain is a measure of the ability of patients to understand and digest numerically presented information so as to make appropriate health decisions and understand risk factors.
Not properly numeracy-assessed patients are prone to make inaccurate and inappropriate decisions for their medical treatments. There are many challenges that the researchers face in designing and developing patient-sensitive numeracy assessment methods. The adaptability of the numeracy assessment is considered to be one of the most important issues to address. The existing methods of numeracy testing do not take confidence as a parameter in consideration for adaptive assessment. Numeracy assessment without confidence is prone to guess work. A better result in measurement is achieved when confidence in the knowledge is also appraised. More importantly, patients may act up on knowledge when they have confidence in it. Thus, we aimed to develop a novel model for Patient Numeracy Assessment based on this parameter.
We proposed a goal-driven Confidence-based model for Patient Numeracy Assessment (C-PNA), which (1) is adaptable to each individual patient, (2) covers the full sets of numeracy skills, and (3) considers confidence. Our adaptive model is based on a conceptual math model. Accordingly, to develop our model, we applied the Confidence Based Learning method for the measurement of confidence and (4) created the item bank, (5) defined the selection algorithm and (6) specified the associated scoring protocol applicable for the assessment of numeracy. To validate the feasibility of our model, we conducted several empirical studies and demonstrated that the results are statistically significant.
We also (7) introduced a novel quality model for the evaluation of patient numeracy assessment methods. The quality model, which is inspired by ISO/IEC 25022, covers both (8) objective and (9) subjective characteristics regarding patient interface with numeracy assessment methods. We further applied this quality model to compare our numeracy assessment methods with the other existing methods. We were able to establish the place of our Confidence-based Patient Numeracy Assessment (C-PNA) method among the other numeracy assessment methods based on the empirical studies we performed. Empirical data provided the evidence for high satisfaction and trust, and significant effectiveness and usage efficiency of our patient numeracy assessment method.
The results of the empirical studies reveal that our model for the assessment of patient numeracy skill could be consequently pertained for Patient Preference Elicitation (PPE) systems. Preliminary research in support of PPE is reported in the thesis. In particular, it focuses on strategies to improve outcome of the treatments and decisions highly depending on patient’s numeracy skill. It will be instrumental in tailoring decision-supporting interventions to particular patient needs.