Czeisler

• What was the aim(Czeisler)?

  to investigate the experience of individuals working on rotating shift patterns
• What was the sample(Czeisler)?

  Experimental group: 85 rotating shift workers at a mineral mining plant in Utah

  Control group: 68 workers on shifts that didn't rotate
• What is phase advance(Czeisler)?

  anti-clockwise rotation of shifts. This means that as the shifts change people will start work earlier and therefore go to bed earlier which will be problematic as they will have to try to go to sleep earlier which is hard.
• What is phase delay(Czeisler)?

  clockwise rotation of shifts. This means that as shifts change people will start to work later and therefore go to bed later which is easier to do. This means that on the first night they will go to bed later but also wake up later so they get the same amount of sleep
• What was the method(Czeisler)?

  Field experiment and questionnaire
• What was the procedure(Czeisler)?

  First, all ppnts completed a job description questionnaire and a schedule preference

  Then, all shift workers changed from their current system (phase advance) to a phase delay system

  3 months after this they completed a questionnaire about their job
• What were the results(Czeisler)?

  In the questionnaire at the start:

  • those on rotating shifts reported more problems and that their schedule changed too often

  In the questionnaire at the end:

  • Workers preferred the phase delay system
  • Staff turnover in the experimental group went down to the same as the control
  • 33 ppnts stayed on the 7-day rotation and 52 went to a 21-day rotation and reported an increase in satisfaction
• What was the conclusion(Czeisler)?

  Designing shift schedules around circadian principles will help to minimise the effects of temporal disruption