P-A-I-N: a four-cluster MMPI typology for chronic pain

A 4-cluster empirically derived MMPI typology for chronic pain sufferers has been demonstrated by combining the results of 10 investigative teams. These MMPI 'types' have been labeled P-A-I-N and appear to have important clinical and demographic correlates. Type P is the most 'psychopathological' looking as nearly all scales are usually elevated. Type P patients are extreme in their claims of physical illness, psychological distress and social maladaptation. Demographic correlates include poor education, high rates of unemployment, and limited household income. Type A is defined by a 'conversion V' on the 'neurotic' triad scales. It has no unique correlates. Type I has elevations on all of the neurotic triad scales and on no others. Type I patients appear to be the most physically infirm with multiple surgeries and hospitalizations. They may not improve physical status with treatment, but appear to benefit psychologically. Type N profiles are 'normal' in that no scale, except perhaps scale K, is often elevated. Type N patients are moderate in their claims of ill health, often are better educated and employed, and appear to respond well to treatment. Classification rules have been proposed to allow patient-typing without a computer. Use of these rules should allow programmatic research into treatment/type interactions even in the ordinary clinical setting. The typology appears well enough established to allow for prospective studies to test theoretical hypotheses drawn from the literature base.