An impact evaluation of a federal mine safety training regulation on injury rates among US stone, sand, and gravel mine workers: an interrupted time-series analysis.
OBJECTIVE
We evaluated the impact of a safety training regulation, implemented by the US Department of Labor's Mine Safety and Health Administration (MSHA) in 1999, on injury rates at stone, sand, and gravel mining operations.


METHODS
We applied a time-series design and analyses with quarterly counts of nonfatal injuries and employment hours from 7998 surface aggregate mines from 1995 through 2006. Covariates included standard industrial classification codes, ownership, and injury severity.


RESULTS
Overall crude rates of injuries declined over the 12-year period. Reductions in incident rates for medical treatment only, restricted duty, and lost-time injuries were consistent with temporal trends and provided no evidence of an intervention effect attributable to the MSHA regulation. Rates of permanently disabling injuries (PDIs) declined markedly. Regression analyses documented a statistically significant reduction in the risk rate in the postintervention time period (risk rate = 0.591; 95% confidence interval = 0.529, 0.661).


CONCLUSIONS
Although a causal relationship between the regulatory intervention and the decline in the rate of PDIs is plausible, inconsistency in the results with the other injury-severity categories preclude attributing the observed outcome to the MSHA regulation. Further analyses of these data are needed.
Monforton
Celeste
C
Department of Environmental and Occupational Health, School of Public Health and Health Services, George Washington University, Washington, DC, USA. celeste.monforton@gwumc.edu
Windsor
Richard
R
D000062:Accidents, Occupational / Q000517:prevention & control* / Q000706:statistics & numerical data*; D006801:Humans; D015994:Incidence; D008906:Mining / Q000331:legislation & jurisprudence*; D017751:Safety Management / Q000331:legislation & jurisprudence* / Q000592:standards; D018582:Sick Leave / Q000706:statistics & numerical data*; D012822:Silicon Dioxide; D014481:United States / Q000453:epidemiology
D012822:Silicon Dioxide
Health Educ Q. 1985 Winter;12(4):315-31
4077544
Occup Med. 1994 Apr-Jun;9(2):127-34
8085196
Am J Ind Med. 2007 Dec;50(12):999-1009
17918223
J Appl Psychol. 2002 Jun;87(3):488-96
12090606
Occup Environ Med. 2004 Aug;61(8):651-60
15258270
Ergonomics. 1999 Jan;42(1):171-82
9973879
J Occup Rehabil. 2005 Dec;15(4):607-31
16254759
Cochrane Database Syst Rev. 2007 Oct 17;(4):CD006251
17943901
Occup Med. 1994 Apr-Jun;9(2):147-58
8085198
Eval Rev. 1996 Jun;20(3):291-312
10182206
Occup Med. 1994 Apr-Jun;9(2):171-88
8085200
Accid Anal Prev. 2000 Nov;32(6):761-9
10994603
Am J Public Health. 2008 Mar;98(3):416-23
18235060
Occup Med. 1994 Apr-Jun;9(2):211-40
8085202
Am J Public Health. 1988 Sep;78(9):1218-9
3407825
Am J Ind Med. 1996 Apr;29(4):289-94
8728126
Am J Ind Med. 1996 Mar;29(3):258-68
8833778
Am J Ind Med. 2005 Mar;47(3):227-36
15712256
Int Arch Occup Environ Health. 2005 Aug;78(7):523-32
15959740
Am J Ind Med. 1993 Mar;23(3):391-406
8503459
Occup Med. 1998 Apr-Jun;13(2):357-79
9589449
Am J Ind Med. 2004 Apr;45(4):371-9
15029570
Am J Public Health. 2002 Sep;92(9):1421-9
12197968
J Occup Environ Med. 2007 Apr;49(4):401-10
17426523
Am J Ind Med. 1998 Aug;34(2):105-12
9651619
Occup Environ Med. 2004 Mar;61(3):239-46
14985519
Fam Pract. 2003 Jun;20(3):333-9
12738704
Fed Regist. 1999 Sep 13;64(176):49548-634
11010710
J Occup Environ Med. 2004 Jan;46(1):10-8
14724473
J Occup Environ Med. 2001 Dec;43(12):1001-10
11765671