Understanding of website usability: Specifying and measuring constructs and their relationships

a r t i c l e i n f o Developing a usable website is pivotal for e-business success. Researchers have devoted effort to develop metrics, guidelines and theories of website usability, yet there still is a lack of consensus on the multifaceted dimensions of website usability and lack of investigation of the nomological networks among website usability constructs. This study first investigated the common dimensions of website usability by integrating the findings of previous studies and a focus group study with website usability experts. Instruments to measure the constructs were developed and empirically validated. Then nomological networks between website usability constructs and between those constructs and online purchase intention and purchase were examined. Three field studies including two questionnaire surveys and a causal mapping analysis were conducted. The research identified ten website usability constructs with strong psychometric properties. A number of nomological networks between usability constructs were discovered, contributing to identification of sources of variances of purchase intention and purchase behavior. Findings of this study are expected to provide useful insights for practitioners to develop more usable websites and for researchers to better assess the effect of website usability on online customer behavior. Within the e-commerce environment, the impact of a web site design on customer purchases cannot be fully understood without an evaluation of the usability of the web site – DeLone and McLean [19, p. 25] Developing usable websites is pivotal for e-business success since online consumers touch, feel, search, and experience products (or services) mainly through websites [18,68]. A usable website has been known to provide a positive attitude toward online stores, increases stickiness and revisit rates, and eventually stimulates online purchase [13,32,50,70]. To make comparisons with competitors' websites, benchmark performance, and plan improvements for designing a more usable website, HCI researchers have devoted effort to define website usability constructs, develop instruments to measure the multifaceted website usability constructs, assess their influences on online customers' attitude or behaviors including satisfaction, loyalty, purchase or revisit intention , and actual purchases [23,30,46]. This has led to a number of metrics, guidelines, and even theories of website usability. However, even with this knowledge and contrary to our expectation , current websites still contain a number of usability problems [9,14,67,68]. Difficult-to-understand content, inconsistent formats, difficulty in navigation, disorientation, lack of interaction and reliability, inefficient search capabilities, and ill-defined help functions are usability problems frequently identified with commercial websites. Regarding …