“…Other difficulties include a lack of validity studies and a lack of normative data, especially among older adults (Conte, 1983). For example, very few instruments have been validated against the physiological measures (i.e., Nocturnal Penile Tumescence [NPT], hormonal data) now used to assess sexual dysfunction (Conte, 1986;Derogatis, 1975Derogatis, , 1978Harbison et al, 1974;Hoon et al, 1976;Rust & Golombok, 1986). In addition, most of the assessment instruments now available tend to be lengthy and difficult t o score, or they do not cover the range of behaviors that are of interest to sexual dysfunction clinics (Rust & Golombok, 1986).…”