The aim of this study was to recurrently follow quality of life in type 1 diabetes patients who have switched from syringe to multiple pen injection treatment. The insulin pen is a simpler automatically preset device for self-injection. Seventy-three consecutive outpatients were initially examined in 1988, 66 of whom were re-examined in 1990. Quality of life was defined as perceived well-being and life satisfaction, globally as well as within key domains and functions, Various status and retrospective change ratings were repeatedly performed by patients and significant others. For a great majority, quality of life status was fairly stable between 1988 and 1990. Nine subjects with recent incidences of severe socio-medical complications accounted for a great deal (41%) of the decline in composite quality of life status recorded, Future-orientation and the conduct of the multiple regimen declined in the major fairly stable patient group as well, Contrary to the change-in-status outcome referred to, the direct retrospective change ratings in 1990 indicated a certain continuing consistent improvement over the last 2 years. It was minor, though, in comparison with the preceding enhancement attributed to the pen. In spite of the divergent mean outcome, the disparate change parameters correlated, The self-rated life quality trends were corroborated by ratings by significant others. To a certain extent, the mean change bias may reflect coping strategies released by and adopted against the strain of the illness. Probably, these primarily coloured the more sensitive direct retrospective change ratings. Some bias may also be due to a lack of sensitivity of the status ratings. However, the differential change assessments may also tease out and illustrate two separate, equally valid, patient perspectives, one on their current situation and another one on how it has changed. The diabetes illness appears reasonably stable in a majority of the subjects over the study interval. There Seem to be some remaining satisfactory quality of life effects of the pen therapy, The study underscores the benefit of undertaking combined retro-/prospective and sufficiently longitudinal analyses with simultaneous dual rating operations, to get the most nuanced overview.