On each life chart, the horizontal line across the middle of the chart represents the baseline (euthymia, neither depressed nor hypomanic or manic) and the dateline. Retrospective life charting is done monthly and prospective ratings are done daily. Hypomania and mania are charted above the dateline, and depression is charted below the dateline, creating a graphical picture of mood fluctuations above and below normal over time. Any hospitalization (for mood) is considered a severe episode and is completely darkened for easy recognition.

  Dr. Kraepelin’s early life chart graphs charted episodes at monthly intervals with color codes (e.g. red for mania, lighter red for hypomania, dark and light blue for severe and mild depression, respectively). Dr. Kraepelin’s early studies found that patients often undergo a progressive increase in cycle frequency, or a decrease in the well interval between episodes; that initial episodes were often triggered by external events, but later episodes emerged spontaneously; and that affective illness tended to continue in families (genetic vulnerability).

  The NIMH-LCM was developed in the 1980’s based on Dr. Kraepelin’s principles of charting the course of affective illness (Roy-Byrne et al., 1985, Acta Psychiatrica Scandinavica [Suppl.] 71: 1–34; Post et al., 1988, Am J Psychiatry 145: 844–848). This method was then further developed, codified, and computerized (Leverich and Post, 1996, Current Review of Mood and Anxiety Disorders 1: 48–61; 1998, CNS Spectrums 3: 21–37). The availability of so many new medications and other treatments for bipolar disorder has made it more important than ever to track the course of illness and the response to treatment. The knowledge of a patient’s past course of illness, such as prior number of episodes, illness pattern, and treatment response, can have a significant impact on the choice of current and future treatment strategies.

Is life charting accurate, however? In other words, is life charting consistent and dependable when repeated (reliability), and does it measure what it is supposed to measure (validity)?

  Two different studies have confirmed both the validity and reliability of the NIMH-LCM. In 1997, Denicoff et al. (J Psychiatric Res; 31: 593–603) found that the Prospective Life Chart (LCM-p) reliability was extremely consistent between two different raters in 27 bipolar patients, over a two-week period of daily ratings by each rater. To assess validity, Denicoff et al. correlated LCM-p depression and mania ratings with other more established rating scales, such as the Hamilton Rating Scale for Depression (HRSD), the Beck Depression Inventory (BDI), the Young Mania Rating Scale (YMRS), and the Global Assessment Scale (GAS). They found statistically significant correlations between the LCM-p depression ratings and the two depression scales (HRSD and BDI), between the LCM-p mania ratings and the YMRS, and between the LCM-p average severity rating and the GAS.

  In a second study (Psychological Med 2000; 30: 1391–1397), Denicoff et al. compared LCM-p ratings in 270 bipolar patients to the Inventory of Depressive Symptomatology-clinician rated (IDS-C) scale, the YMRS, and the Global Assessment of Functioning (GAF) scale. Again, the validity of the NIMH-LCM was confirmed, this time in a study with a much larger number of patients. Statistically significant correlations were found between severity of depression ratings on the LCM-p and the IDS-C, between LCM-p mania ratings and the YMRS, and between LCM-p average severity of illness ratings and the GAF.