William Masters and Virginia Johnson’s work is comparative with that of Alfred Kinsey in two ways. Firstly, they were relative contemporaries of Kinsey’s time (Kinsey published his Kinsey Reports in 1948 and 1953, while Masters and Johnson met in 1957). This is significant in that all three approached a very taboo subject of their time period. Secondly, all focused on uncovering human sexuality, and made efforts to share their collected information with the world through their published works. Their conclusions were similar—that sex is a natural and healthy occurrence in humans, and one that can “be enjoyed as a source of pleasure and intimacy.” However, it is in their methods of approach to the subject of human sexuality that these two teams differ.
Whereas Kinsey used surveys of individuals across the United States to determine “the frequency with which certain behaviors occurred in the population” (ex. sexual orientation, extramarital affairs, etc.), Masters and Johnson sought to conduct a more scientific study into the actual physiology of sex and sexual arousal. Their research, rather than being conducted out in the field via interviews, was conducted in laboratories, with data being accumulated by observing physical responses to sexual stimulation. From this research the couple published their four-part model of the “human sexual response cycle,” which describes the rise and fall of sexual arousal in humans (Excitement, Plateau, Orgasm, and Resolution) (Source).
Compared to Kinsey, Masters and Johnson were similarly interested in so-called “deviant” sexual behaviors (those that would be considered out of the “norm”), but unlike him they categorized homosexuality as a sexual dysfunction. The two even ran a conversion therapy program for nine years. (Conversion therapy aims to convert homosexuals to heterosexuals.) This was not an uncommon medical view of the time, as homosexuality was classified as a psychological disorder in the Diagnostic and Statistical Manual of Mental Disorders until 1977 (Source). On the other hand, Kinsey maintained a much more liberal view of sexuality, concluding that "there was little that could be called 'normal' in sexual behavior" due to the varying tastes of the thousands of individuals surveyed for his study (Kinsey Report, eNotes).
In conclusion, the three were similar in their area of study, though Masters and Johnson focused more on a scientific approach to sex than did Alfred Kinsey.