Graph of Daily Min, Mean and Maximum PEF

The upper panel of the plot shows the daily difference between maximum and minimum PEF expressed as a percentage of the predicted value (the Diurnal Variation - D.V).

The middle panel centre section shows the daily maximum (blue dashes), mean (black bars) and minimum (red dashes) PEF. "Days" start with the first reading at work, and continue to the last reading before work on the following day, or to the reading after waking for days with no work (Day interpreted), as the waking reading relates to exposures on the preceding day.

The middle panel, top section shows Oasys complex scores. A complex is a period at work, with preceding and succeeding periods away from work (a rest-work-rest complex), or its counterpart with a central period away from work (a work-rest-work complex). Oasys-2 uses a discriminant analysis to estimate the likelihood of each complex showing an occupational effect. 1 = "No", 2 = "1-49% Probability", 3 = "50-99% Probability" and 4 = "Yes". The scores are generally conservative (underscoring) compared with expert interpretation.

The bottom panel shows the day of week, date of start and finish of each "day interpreted" day, the number of readings included in each "day", the number of hours worked each "day", and any additional comments (see code at bottom of right panel)

Graph of Daily Min, Mean and Maximum PEF

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