APPENDIX 2 Segmented regression analysis of interrupted ... · APPENDIX 2 Segmented regression...

APPENDIX 2 Segmented regression analysis of interrupted time series

data

Figure 3: Segmented regression analysis of interrupted time series data; redrawn from MacDougall

(2005)

REFERENCE: MacDougall, C. and R. E. Polk (2005). "Antimicrobial Stewardship Programs in Health Care Systems."

Clinical Microbiology Reviews 18(4): 638-656.

APPENDIX 3 Observed versus predicted counts (lagged vacation

period shown by black rectangle)

APPENDIX 4: Graph of Pearson residuals versus predicted values from

the models

APPENDIX 5: Results of sensitivity analysis (no lag)

The GENMOD Procedure

State=ACT

Friday, September 27, 2019 11:33:50 AM 1

Model Information

Data Set WORK.WEEK19

Distribution Negative Binomial

Link Function Log

Dependent Variable Count Count

Number of Observations Read 17

Number of Observations Used 17

Criteria For Assessing Goodness Of Fit

Criterion DF Value Value/DF

Deviance 11 18.6532 1.6957

Scaled Deviance 11 18.6532 1.6957

Pearson Chi-Square 11 18.6078 1.6916

Scaled Pearson X2 11 18.6078 1.6916

Log Likelihood 12958.6076

Full Log Likelihood -82.5194

AIC (smaller is better) 179.0389

AICC (smaller is better) 191.4833

BIC (smaller is better) 184.8714

Algorithm converged.

Analysis Of Maximum Likelihood Parameter Estimates

Parameter DF Estimate

Standard

Error

Wald 95%

Confidence

Limits

Wald

Chi-Square Pr > ChiSq

Intercept 1 4.0531 0.1278 3.8026 4.3035 1006.15 <.0001

wk 1 0.2025 0.0261 0.1513 0.2537 60.08 <.0001

Vacation 1 -0.3423 0.2226 -0.7786 0.0940 2.36 0.1241

postvac 1 -0.9092 0.2287 -1.3574 -0.4611 15.81 <.0001

vacwk 1 -0.3377 0.2493 -0.8264 0.1509 1.84 0.1755

postwk 1 -0.2126 0.0516 -0.3138 -0.1115 16.97 <.0001

Dispersion 1 0.0265 0.0123 0.0107 0.0657


State=ACT


Note: The negative binomial dispersion parameter was estimated by maximum likelihood.


State=NSW


Model Information



Link Function Log






Deviance 11 17.2499 1.5682












Standard

Error

Wald 95%

Confidence

Limits

Wald


Intercept 1 7.1594 0.0477 7.0658 7.2529 22483.8 <.0001

wk 1 0.2513 0.0100 0.2317 0.2708 633.27 <.0001

Vacation 1 -0.3949 0.0911 -0.5735 -0.2163 18.78 <.0001

postvac 1 -1.1929 0.0903 -1.3698 -1.0160 174.71 <.0001

vacwk 1 -0.4404 0.1035 -0.6432 -0.2376 18.12 <.0001

postwk 1 -0.2610 0.0200 -0.3003 -0.2218 169.75 <.0001

Dispersion 1 0.0052 0.0019 0.0025 0.0106


State=NSW




State=QLD


Model Information



Link Function Log






Deviance 11 16.8421 1.5311












Standard

Error

Wald 95%

Confidence

Limits

Wald


Intercept 1 6.3271 0.0752 6.1797 6.4745 7079.13 <.0001

wk 1 0.2307 0.0178 0.1958 0.2655 168.36 <.0001

Vacation 1 -0.2432 0.1418 -0.5211 0.0348 2.94 0.0864

postvac 1 -0.4808 0.1442 -0.7635 -0.1981 11.11 0.0009

vacwk 1 -0.3933 0.1582 -0.7034 -0.0833 6.18 0.0129

postwk 1 -0.1853 0.0284 -0.2409 -0.1296 42.59 <.0001

Dispersion 1 0.0120 0.0042 0.0060 0.0240


State=QLD




State=SA


Model Information



Link Function Log






Deviance 11 16.7721 1.5247












Standard

Error

Wald 95%

Confidence

Limits

Wald


Intercept 1 7.5506 0.0921 7.3701 7.7311 6722.28 <.0001

wk 1 -0.2042 0.0195 -0.2424 -0.1660 109.98 <.0001

Vacation 1 0.3417 0.1931 -0.0368 0.7202 3.13 0.0768

postvac 1 0.2312 0.1875 -0.1362 0.5986 1.52 0.2174

vacwk 1 0.0497 0.2247 -0.3907 0.4901 0.05 0.8251

postwk 1 0.2627 0.0426 0.1792 0.3463 37.96 <.0001

Dispersion 1 0.0225 0.0083 0.0109 0.0464


State=SA




State=VIC


Model Information



Link Function Log






Deviance 11 17.1907 1.5628












Standard

Error

Wald 95%

Confidence

Limits

Wald


Intercept 1 7.2885 0.0618 7.1674 7.4095 13925.1 <.0001

wk 1 0.1199 0.0148 0.0908 0.1490 65.38 <.0001

Vacation 1 0.0094 0.1177 -0.2212 0.2400 0.01 0.9364

postvac 1 -0.6088 0.1189 -0.8418 -0.3758 26.22 <.0001

vacwk 1 -0.1639 0.1303 -0.4194 0.0915 1.58 0.2085

postwk 1 -0.1321 0.0227 -0.1765 -0.0876 33.95 <.0001

Dispersion 1 0.0081 0.0030 0.0040 0.0166


State=VIC




State=WA


Model Information



Link Function Log






Deviance 11 16.9313 1.5392












Standard

Error

Wald 95%

Confidence

Limits

Wald


Intercept 1 5.1100 0.2033 4.7115 5.5085 631.72 <.0001

wk 1 0.1450 0.0442 0.0584 0.2316 10.78 0.0010

Vacation 1 -0.9990 0.3819 -1.7475 -0.2505 6.84 0.0089

postvac 1 -2.2228 0.3927 -2.9924 -1.4531 32.04 <.0001

vacwk 1 -0.4136 0.4234 -1.2434 0.4162 0.95 0.3286

postwk 1 -0.3356 0.0874 -0.5068 -0.1644 14.76 0.0001

Dispersion 1 0.0835 0.0307 0.0406 0.1718


State=WA



State=ACT


Plot of predicted*week. Symbol used is 'e'. Plot of Count*week. Symbol used is 'o'. | | 300 + | e | | | | | 250 + e | o | e o o | o | e | o e e e P | o e e e r 200 + e | e d | i | c | o o t | e | e d 150 + | V | o a | e l | o u | o e | e 100 + | | e | | e | | e o 50 + | | o | | | | 0 + | ---+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+-- 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 week NOTE: 4 obs hidden.

State=NSW


Plot of predicted*week. Symbol used is 'e'. Plot of Count*week. Symbol used is 'o'. 10000 + | | e | | 9000 + | | o | e | 8000 + | | | e | P 7000 + o r | e e | d | o i | e e o c 6000 + e e e t | e e e | o o d | | o V 5000 + a | l | e u | e | 4000 + o | | e | | 3000 + | e | | | e 2000 + | | e | | e 1000 + ---+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+-- 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 week NOTE: 9 obs hidden.

State=QLD


Plot of predicted*week. Symbol used is 'e'. Plot of Count*week. Symbol used is 'o'. 5000 + | | | | e 4500 + o o | o e | o | e | 4000 + e | o | e | o | e P 3500 + e r | e | d | i | c 3000 + t | e | e e d | | o o V 2500 + a | e l | u | e e | o o 2000 + | | e | | 1500 + | e | | | e 1000 + o | e | o | e | e 500 + o ---+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+-- 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 week NOTE: 4 obs hidden.

State=SA


Plot of predicted*week. Symbol used is 'e'. Plot of Count*week. Symbol used is 'o'. 2000 + | | e | o | 1800 + | | | | 1600 + o o | e | | | P 1400 + r | e | d | e i | c 1200 + t | e | d | | e V 1000 + a | o l | u | e | e 800 + | o | | e | 600 + | e | o | o | o e e 400 + | e e o | e e e | o e e | e o o 200 + ---+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+-- 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 week NOTE: 5 obs hidden.

State=VIC


Plot of predicted*week. Symbol used is 'e'. Plot of Count*week. Symbol used is 'o'. | | 4000 + | | e | | e | | 3500 + | | e | o | | P | r 3000 + e e | o d | i | o c | t | o e o e e e | e e d 2500 + o e e | e V | e o a | o l | o u | e | o e 2000 + | | e | | o | e | 1500 + | e | | | o | | 1000 + | ---+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+-- 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 week NOTE: 5 obs hidden.

State=WA


Plot of predicted*week. Symbol used is 'e'. Plot of Count*week. Symbol used is 'o'. | | 600 + | | | | | e | 500 + | o | | e | | P | o r 400 + e e | d | o i | c | o e t | o e | d 300 + o e | V | a | e l | u | e e | e 200 + | e | e e | | | o | 100 + o | o e | e | o e o | e e | e | 0 + | ---+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+-- 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 week NOTE: 6 obs hidden.


Plot of pearson*predicted. Legend: A = 1 obs, B = 2 obs, etc. | | 2.5 + | | A A | A 2.0 + A A | A | A | A 1.5 + A A | A A | A A | B A P 1.0 + A A A e | A a | A A A A A r | B AA s 0.5 + A o | A n | A A A A B | A A R 0.0 + BCAA A A A A A A A e | A AA A A A s | A A A i | A A A A A A d -0.5 + A A A u | AA A A A A a | A A A l | A A -1.0 + A A | A A A | AA AA A | -1.5 + A A A | A A | A | A -2.0 + A | A | | -2.5 + | --+-----------+-----------+-----------+-----------+-----------+-----------+-----------+-----------+-----------+-----------+-- 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 Predicted Value

APPENDIX 2 Segmented regression analysis of interrupted ... · APPENDIX 2 Segmented regression...

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