Several investigations of schizophrenia have used a 3-phase model to summarize the life-course of this disorder (onset, course, and outcome). Onset here is classified as either acute (e.g. < 6 months) or gradual (sometimes deemed “insidious”  as it reflects slower deterioration and poorer recovery). Course refers to the post-onset years as being either undulating (highs and lows) or smooth. Outcome refers to the last two years of data gathering.
    The study population comprised 128 people who were first admitted for schizophrenia to a mental hospital in Alberta in 1963 and followed until 1997 or death. Information was collected from the patients themselves, hospital files, treatment records, and family members. A four-point rating system (0 to 3) was used to depict respondent information for each year when data were collected.  Thus, 3 = Hospitalization due to mental illness; 2 = a psychotic episode verified by a professional (no hospitalization); 1= some psychiatric symptoms and/or outpatient counselling; and 0= Absence of psychiatric symptoms. These scores were collapsed to produce the onset, course and outcome dichotomies described above, producing eight possible life-span classifications (2x2x2). 
   An example of each classification was drawn from our sample and presented in the accompanying figure. Overall, we found that acute and gradual onsets were essentially equally (51% acute and 49% gradual), with undulation dominating course at 64%, and outcomes being about equal (52% being poor).
   Our mathematical descriptions of onset, course, and outcome produced profiles that did not closely match the results of other investigations, largely due to differing methods. Notably, the result of our approach suggests that even for those with good eventual outcomes, life is often very difficult.

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