Table 1 Results from fixed effects linear models comparing the effects of BDLE with STLE
|  | Mean STLE | Mean BDLE | Estimated mean Difference | 95% CI | P Value | Cohen’s d |
|---|---|---|---|---|---|---|
Work Diary | ||||||
 Number of Caffeinated drinks | ||||||
  E vs E | 2.15 | 1.19 | 0.21 | -0.42 to 0.84 | 0.508 | 0.636 |
  N vs N | 2.11 | 1.73 | -0.37 | -0.70 to -0.04 | 0.027* | 0.367 |
  E.N. vs E.N | 2.14 | 1.49 | -0.09 | -0.42 to 0.24 | 0.582 | 0.490 |
 How stressful was your shift? (range 1–5) a | ||||||
  E vs E | 2.56 | 2.31 | -0.32 | -0.92 to 0.27 | 0.277 | 0.225 |
  N vs N | 2.95 | 2.70 | -0.30 | -0.88 to 0.28 | 0.312 | 0.248 |
  E.N. vs E.N | 2.74 | 2.53 | -0.24 | -0.65 to 0.17 | 0.246 | 0.202 |
 How sleepy were you during the shift? (range 1–5) a | ||||||
  E vs E | 2.46 | 3.03 | 0.74 | 0.06 to 1.42 | 0.034* | 0.486 |
  N vs N | 2.86 | 3.07 | 0.22 | -0.34 to 0.77 | 0.440 | 0.204 |
  E.N. vs E.N | 2.65 | 3.06 | 0.42 | 0.002 to 0.05 | 0.048 | 0.372 |
 How positive did you feel during the shift? (range 1–5) a | ||||||
  E vs E | 3.81 | 3.84 | 0.10 | -0.33 to 0.53 | 0.654 | -0.037 |
  N vs N | 3.25 | 3.53 | -0.13 | -0.49 to 0.23 | 0.486 | -0.382 |
  E.N. vs E.N | 3.55 | 3.67 | -0.34 | -0.30 to 0.24 | 0.804 | -0.150 |
 How negative did you feel during the shift? (range 1–5) a | ||||||
  E vs E | 1.62 | 1.63 | 0.10 | -0.45 to 0.65 | 0.723 | -0.011 |
  N vs N | 1.70 | 1.57 | -0.09 | -0.46 to 0.28 | 0.619 | 0.194 |
  E.N. vs E.N | 1.66 | 1.60 | -0.01 | -0.32 to 0.30 | 0.943 | 0.076 |
Sleep Diary | ||||||
 Time in Bed, min | ||||||
  E vs E | 507.00 | 481.00 | 31.47 | -198.37 to 261.30 | 0.785 | 0.088 |
  N vs N | 488.00 | 529.00 | 98.99 | -177.39 to 375.37 | 0.476 | -0.104 |
  E.N. vs E.N | 499.00 | 508.00 | 73.34 | -102.50 to 249.17 | 0.410 | -0.025 |
 Sleep Period Time, min | ||||||
  E vs E | 410.00 | 405.00 | -18.19 | -70.74 to 34.37 | 0.491 | 0.074 |
  N vs N | 361.00 | 399.00 | 65.30 | -45.14 to 175.73 | 0.241 | -0.238 |
  E.N. vs E.N | 390.00 | 401.00 | 34.18 | -28.13 to 96.48 | 0.279 | -0.093 |
 Total Sleep Time, min | ||||||
  E vs E | 356.00 | 371.00 | -7.57 | -61.88 to 46.74 | 0.781 | -0.203 |
  N vs N | 328.00 | 376.00 | 6.11 | -41.30 to 173.52 | 0.223 | -0.314 |
  E.N. vs E.N | 344.00 | 374.00 | 39.25 | -21.84 to 100.33 | 0.206 | -0.239 |
 Sleep Onset Latency, min | ||||||
  E vs E | 23.31 | 24.54 | -3.09 | -20.29 to 14.11 | 0.720 | -0.046 |
  N vs N | 14.68 | 8.85 | -2.25 | -13.15 to 8.65 | 0.680 | 0.334 |
  E.N. vs E.N | 19.64 | 15.94 | -2.82 | -12.32 to 6.67 | 0.557 | 0.162 |
 Wake After Sleep Onset, min | ||||||
  E vs E | 34.07 | 9.11 | -10.80 | -34.95 to 13.36 | 0.374 | 0.804 |
  N vs N | 18.65 | 13.62 | 1.43 | -14.32 to 17.19 | 0.856 | 0.194 |
  E.N. vs E.N | 27.43 | 11.58 | -3.58 | -17.08 to 9.92 | 0.600 | 0.537 |
 Early Morning Awakening, min | ||||||
  E vs E | 15.74 | 11.04 | -5.02 | -16.61 to 6.57 | 0.389 | 0.287 |
  N vs N | 67.68 | 114.00 | 54.63 | -129.70 to 238.96 | 0.555 | -0.172 |
  E.N. vs E.N | 37.50 | 67.68 | 28.12 | 67.21 to 123.45 | 0.560 | -0.156 |
 Sleep Efficiency, % | ||||||
  E vs E | 77.84 | 83.83 | 0.66 | 11.48 to 12.80 | 0.913 | -0.378 |
  N vs N | 78.31 | 79.79 | 0.09 | -11.44 to 11.63 | 0.987 | -0.083 |
  E.N. vs E.N | 78.03 | 81.61 | 0.67 | -7.39 to 8.73 | 0.870 | -0.214 |
 Nightly Awakenings, No | ||||||
  E vs E | 1.60 | 1.39 | -0.41 | -1.26 to 0.44 | 0.336 | 0.152 |
  N vs N | 1.26 | 1.35 | 0.38 | -0.37 to 1.12 | 0.313 | -0.068 |
  E.N. vs E.N | 1.45 | 1.37 | 0.05 | -0.50 to 0.59 | 0.864 | 0.060 |
 Sleep Quality a | ||||||
  E vs E | 3.05 | 3.48 | 0.23 | -0.65 to 1.11 | 0.601 | -0.397 |
  N vs N | 3.29 | 3.29 |  < 0.00 | -0.52 to 0.52 | 0.991 | 0.000 |
  E.N. vs E.N | 3.15 | 3.38 | 0.10 | -0.37 to 0.57 | 0.671 | -0.243 |
Actigraphy | ||||||
 Sleep Period Time, min | ||||||
  E vs E | 410.00 | 402.00 | 11.65 | -48.65 to 71.95 | 0.698 | 0.123 |
  N vs N | 369.00 | 389.00 | 67.18 | -53.89 to 188.26 | 0.269 | -0.135 |
  E.N. vs E.N | 393.00 | 395.00 | 53.19 | -15.89 to 122.28 | 0.129 | -0.020 |
 Total Sleep Time, min | ||||||
  E vs E | 362.00 | 345.00 | 1.86 | -56.37 to 60.09 | 0.949 | 0.283 |
  N vs N | 342.00 | 366.00 | 68.88 | -42.37 to 180.13 | 0.218 | -0.329 |
  E.N. vs E.N | 353.00 | 356.00 | 50.30 | -14.77 to 115.37 | 0.128 | -0.221 |
 Wake After Sleep Onset, min | ||||||
  E vs E | 52.00 | 57.24 | 7.72 | -16.28 to 31.70 | 0.518 | -0.131 |
  N vs N | 26.55 | 22.89 | -1.79 | -22.26 to 18.67 | 0.860 | 0.126 |
  E.N. vs E.N | 40.57 | 39.40 | 2.15 | -12.57 to 16.86 | 0.772 | 0.031 |
 Sleep Periods, No | ||||||
  E vs E | 14.10 | 13.79 | -2.23 | -5.13 to 0.68 | 0.130 | 0.070 |
  N vs N | 11.67 | 11.76 | 1.64 | -2.86 to 6.14 | 0.464 | -0.017 |
  E.N. vs E.N | 13.10 | 12.84 | 0.13 | -2.45 to 2.71 | 0.919 | 0.053 |