- Email: [email protected]
Safety belt use in New Hampshire
Joumal ofSqfety Research Vol. 23, pp. 147-150,19!92 0 I992 National Safety Council and Pergamon Press Ltd.
0022-4375192 $5.00 + .OO Printed in the USA
Safety Belt Use in New Hampshire Allan F. Williams
and JoAnn IS.Wells
Shoulder belt use by drivers and right-front passengers was observed in four New Hampshire cities in May 1991. Driver belt use ranged from 28% to
45% in the four cities and was 36% overall; passenger belt use was 33% overall. These results contrast with those in a 1990 New Hampshire state survey, which reported statewide driver and passenger belt use rates of 52% and 54%, respectively. New Hampshire does not have a safety belt use law. The present results suggest that New Hampshire has belt use rates typical of the other New England states without laws. Baaed on the experience of other states with laws, it is likely that enactment of a belt use law would increase use considerably.
~ODU~ON The first state safety belt use law in the United States was enacted in New York in 1984. Over the next few years, most states enacted belt use laws, and by 1991 ~~-eight states and the District of Columbia required safety belt use. Belt use in the United States was very low - 15% or less - before the This work was supported by the Insurance Institute for Highway Safety. Allan F. Williams is Vice President for Research with the InsuranceInstitute for Highway Safety; he holds a Ph.D. in Social Psychology from Harvard University, Dr. Willis has published more than 100 scientific papers in a wide variety of research areas including alcohol, drugs and driving; seat belt use; and preventing motor vehicle deaths and injuries among teenagers and children. He has investigated the roles of driver education, licensure age, and restraintuse in motor vehicle crashes. JoAnn K. We& is Research Associate with the kIsuIZXe Institute for Highway Safety; she holds a B.S. from Emmanuel College. Ms. Wells has published several articles concerning various aspects of seat belt and child restraint use, including seat belt use by teenagers and use of automatic seat belts. Her research interests also include innovative methods and programs to reduce alcoholimpaireddriving. Fall 1992/V&me 23/Mmber 3
state laws were enacted (Perkins, Cynecki, & Goryl, 1984). The laws have typically resulted in substantial increases in use rates and reductions in occupant deaths (Skinner & Hoxie, 1988; Campbell, Stewart, & Campbell, 1987; Lund, Zador, & Pollner, 1987). Al~ough belt use has not approached the 80-9096 use rates achieved in some countries, belt use is now at 40-50% in many states with laws and some have use rates over 60% (NHTSA, 1990a). States with primary enforcement laws, which allow motorists to be stopped and ticketed for a belt use violation, generally have higher use rates than states with secondary laws, which require a motorist to first be stopped for some other traffic offense (Campbell, 1987). As belt use has increased in states with laws, it has also increased somewhat in states without laws; however, it is generally lowest in states without laws. The best evidence for trends in belt use comes from the ongoing 19city survey conducted for the National Highway Traffic Safety Administration (NHTSA). In the four cities without belt use laws throughout the 1985-1990 period (Birmingham, FargolMoorhead, Phoenix, and 147
Providence), driver belt use increased from 17% to 36%. Driver belt use was 54% in the 14 cities with laws and 36% in the five cities without laws in the 1990 19-city survey (NHTSA, 1990b). Many states conduct their own safety belt use surveys, using a variety of methods. New Hampshire, a state without a belt use law, has been conducting statewide surveys since 1984, based on guidelines established by the NHTSA in 1983 (Phillips, 1983, May; NHTSA, 199Oc). According to these surveys, driver belt use increased from 16% in 1984 to 52% in 1990 (State of New Hampshire Highway Safety Agency, 1990, October). In the 10 counties in New Hampshire, reported belt use ranged narrowly in 1990 from 48% to 54%. Reported belt use was about the same on highways (53%) as on local roads (51%), and about the same in urban (53%) as in rural areas (51%). Safety belts were reported to be used by 55% of the 466 right-front passengers observed. These results are higher than typically reported for nonlaw states. The New England region includes 4 of the 10 states without safety belt use laws. The only New England state with a belt use law at the time of this survey was Connecticut;* driver belt use in Connecticut in 1990 was reported to be 59% (Connecticut Department of Transportation, 1988, January). Belt use for 1990 in Vermont was reported to be 39% (Vermont S.E.A.T. Coalition, 1990) and in Massachusetts it was reported to be 29% (Hingson, 1990). In the NHTSA 19-city survey, use in Boston was 33% in 1990. In the last survey undertaken in Maine in 1986, belt use was 23% (Hungerford, Kovenock, & Sorg. 1986). Rhode Island has not had a recent statewide survey, but in the 19-city survey, conducted in 1990 while Rhode Island did not have a law, use in Providence was 27% (NHTSA, 1990b). In comparison to the experience in these four nonlaw states, the belt use rate reported for New Hampshire is quite high. It is uncommon for belt use to be higher in jurisdictions without belt use laws than in those with laws. In the 19-city survey, Phoenix (without a law)
*Rhode Island passed a seat belt use law effective June 1991. 148
had a higher use rate in 1990 than five of the 14 cities surveyed in which belt use was required. However, none of the other four cities without laws had a use rate as high as the lowest rate among the 14 cities with laws. Belt use rates are influenced by factors other than mandatory use laws. For example, use is strongly correlated with socioeconomic status (Lund, 1986). However, New Hampshire is not markedly different from its neighboring New England states in terms of socioeconomic factors (Bureau of the Census, 1990). The coordinator of the New Hampshire Highway Safety Agency attributes the state’s reported high rate achieved without a law to safety belt education and the “basic common sense and intelligence” of New Hampshire motorists, and he says that they intend to increase belt use further using an educational approach (State of New Hampshire, 1990, October). Other New England states have provided safety belt education as well, but New Hampshire’s reported results are anomalous within the geographic region. In an attempt to verify these results, belt use surveys were conducted in four New Hampshire cities in the Spring of 1991. METHODS
Shoulder belt use by drivers and right front passengers was observed in four New Hampshire cities in the southeastern part of the state in May 1991. Nashua (population 81,000) and Manchester (population 102,800) are in Hillsboro County; Concord (population 35,800) is in Merrimack County; Rochester (population 24,700) is in Strafford County. Observations were made at 36 sites: 12 each in Nashua and Manchester and six each in Concord and Rochester. Sites were at intersections with traffic lights, stop signs, or yield signs, and high volumes of traffic. Data were collected once at a site either at morning rush hour (7:00-9:00 a.m.), evening rush hour (4:00-6:30 p.m.), or midday (1l:OO a.m.-l :30 p.m.). Observers were located on the side of the observed vehicle opposite the driver and observed and recorded shoulder belt use of drivers and right-front passengers as vehicles slowed or stopped at the traffic signal. Shoulder belt use Journal of Safety Research
Rochester roads as in the New Hampshire state survey (23%) compares to the 51% driver belt use rate for &afford County reported in the New Hampshire state survey.
was indicated only if the belt was correctly positioned and fastened. For example, if the belt was merely draped over the shoulder and unfastened, or fastened behind the back or under the arm, it was coded as shoulder belt not used. Passenger cars, vans, pickups, and utility vehicles with New Hampshire license plates were observed, as in the New Hampshire statewide survey.
DISCUSSION The survey conducted in 1990 by the state of New Hampshire reported a statewide belt use rate of 528, with belt use showing very little variation by county or by type of road or type of locale. In contrast, the present survey conducted at 36 sites in four southeastern New Hampshire cities, found a driver belt use rate of 36%. Belt use was 50% or greater at only three of the 36 sites and at one of the 11 sites common to both surveys. Both surveys included the same types of vehicles and types of sites. Subsequent to completion of the present study, New H~pshire officials provided the authors with further details on their observation techniques and demonstrated these techniques. The state survey counted occupants as restrained if they were using belts incorrectly (e.g., under the arm), whereas in this study such occupants were classified as unrestrained because no protection was being provided. This different procedure would account for a small part of the difference in belt use rates. The main reason for the higher use rates found by New Hampshire’s survey appears to be that in the state survey an attempt was made to observe all passing vehicles. In most
RESULTS Safety belt use observations were made on 25,003 drivers and 5,930 right-front passengers in the four cities. Table 1 indicates that driver belt use rates ranged from 28% in Rochester to 45% in Concord and was 36% overall. Passenger belt use rates were slightly lower, 33% overall. Driver belt use rates at all 36 sites ranged from 20% to 59%. At only three sites was use 50% or higher. Driver belt use in Manchester (35%) and Nashua (37%) compares to a driver belt use rate of 52% in Hillsboro County reported in the New Hampshire state survey. At Manchester and Nashua sites in the present survey located on the same roads (though not necessarily at the same intersections) as in the New Hampshire state survey, belt use was 33%. In the present survey, driver belt use was 45% in Concord and 48% on the same roads as those used in the New H~psh~e state survey in Merrimac County, where use was reported at 52%. In the present survey, driver belt use in Rochester (28%) and on the same
TABLE 1 PERCENT SHOULDER BELT USE IN tiEW HAMPSHIRE, MAY 1991
Dlk.9fS
Number C&
CG%SXd
Rlpht-Ftont
Total
Possen~~tr
ot
stes
Peccent
(W
Percent
6
45
(4.274)
(Nf
PerCMM
39
(393)
44
(5.213)
(1.973)
3s
(10.437)
(NO
h4anchedel
12
33
w-4>
36
Nashua
12
37
(7.776)
32
(1.5m
35
(9.436)
Rochester
4
28
(4.469)
26
(1 .W)
28
(5‘847)
36
36
(25.003)
33
(5.930)
36
(30.933)
AH Cillss
Foil 199.2hbIume 23/iVumber 3
cases, shoulder belt use will be easily and quickly apparent even in fast-moving vehicles and thus vehicles with belt users will tend to be included in the survey. However, confinning the absence of belt use tends to take more time, and in a stream of moving vehicles there will be more cases in which the observer is uncertain as to belt use. The techniques used by the state officials call for skipping vehicles where there is uncertainty. These procedures are thus likely to provide an overestimate of the true use rate. In contrast, only cars that are slowed or stopped at traffic lights or stop signs were observed for this study, so that use or nonuse could be clearly established in each car viewed. The authors also observed belt use at two sites in Nashua and two sites in Rochester at the exact locations as in the state survey, subsequent to the present study, and found belt use rates of 20-30%, whereas in the state survey use rates were reported to be 40-50% at these sites. In most states, including New Hampshire, belt use observation techniques are based on guidelines provided by the NHTSA. It is suggested that these guidelines be made more explicit to ensure that accurate use rates are obtained and that observation techniques are applied consistently across states. The present results suggest that New Hampshire has use rates typical of a state without a belt use law. Presumably, enactment of a belt use law would, as in other states, increase use considerably. The National Highway Traffic Safety Administration has set a national goal of 70% belt use by 1992. A key component of the program is to publicize and enforce safety belt use laws. Studies here and abroad have repeatedly shown that the combination of publicity and law enforcement are necessary to raise safety belt use rates to high levels. The use of educational approaches alone, as advocated by some New Hampshire officials, has been tried throughout the world, but evaluations consistently show that such programs do not work. Clearly, meeting the NHTSA goal without a mandatory use law will be problematic for states such as New Hampshire.
150
REFERENCES Bureau of the Census. (1990). Statistical abstract of the United States 1990. Washington, DC: U.S. Government Printing office. Campbell, B. J. (1987). The relationship of seat belt law enforcement to level of belt use (HSRC-TR72). Chapel Hill, NC: University of North Carolina Highway __. Safety Research Center. Campbell, B. J., Stewart, J. R., & Campbell, F. A. (1987). 1985-1986 experience with belt laws in the United States. Chanel Hill. NC: Universitv of North Carolina
Highway Safety Research Center. _ Connecticut Department of Transportation, Office of Highway Safety. (1988, January). Safety belt law: O&pant protection program. Wethersfieid Cfz Author. Hingson, R. (1990). Comments on safety belt use, occupant injury and public attitudes about safety belts and‘belt laws in Massachusetts (Memorandum to Governor’s
Highway Safety Bureau Occupant Protection Program Evaluation). Boston, MA. Hungerford, D., Kovenock, D., & Sorg, J. (1986). Maine seat belt use observation study. Grono, ME: Northeast Research. Lund, A. K. (1986). Voluntary seat belt use among U.S. drivers: Geographic, socioeconomic, demographic variation. Accident Analysis and Prevention, 18, i3-50. Lund, A. K., Zador, P., & Palmer, J. (1987). Motor vehicle occupant fatalities in four states with seat belt use laws. SAE 870224. Warrendale, PA: Society of Automotive
Engineers. National Highway Traffic Safety Administration (NHTSA). (1990a). Observed safety belt use statistics by state. Washington, DC: Author. National Highway Traffic Safety Administration (NHTSA). (1990b). Use of automatic safety belt systems in 19 cities. Washington, DC: Author. National Highway Traffic Safety Administration (NHTSA). (199Oc).Belt use guidelines. Washington, DC: U.S. Dept. of Transportation. Perkins, D. D., Cynecki, M. J., & Goryl, M. E. (1984). Restraint system usage in the traffic population (DGT HS 806 582). Washington, DC: U.S. Department of Transportation, National Highway Traffic Safety Administration. Phillips. B. M. (1983, May). Restraint system usage in traffic oomdation CDoT HS 806-424). Washington, DC U.S. Department of Transportation, .NationalHighway Traffic Safety Administration. Skinner, D., & Hoxie, P (1988). Effects of seat belt laws on highway fatalities: Update - April 1988. (Project Memorandum DOT-TSC-HS870-PM-88-5). Washington, DC: National Highway Traffic Safety Administration. State of New Hampshire. (1990, October). Press release accompanying
statewide
seat belt survey results.
Concord, NH: Highway Safety Agency. State of New Hampshire Highway Safety Agency. (1990, October). I990 safetv belt survev. Concord, NH: Highway’Safety Agency. Vermont S.E.A.T. Coalition. (1990). Safety belt use in Vermont: Observational study. Burlington, VT: Vermont S.E.A.T. Coalition.
Journal of Safety Research
0022-4375192 $5.00 + .OO Printed in the USA
Safety Belt Use in New Hampshire Allan F. Williams
and JoAnn IS.Wells
Shoulder belt use by drivers and right-front passengers was observed in four New Hampshire cities in May 1991. Driver belt use ranged from 28% to
45% in the four cities and was 36% overall; passenger belt use was 33% overall. These results contrast with those in a 1990 New Hampshire state survey, which reported statewide driver and passenger belt use rates of 52% and 54%, respectively. New Hampshire does not have a safety belt use law. The present results suggest that New Hampshire has belt use rates typical of the other New England states without laws. Baaed on the experience of other states with laws, it is likely that enactment of a belt use law would increase use considerably.
~ODU~ON The first state safety belt use law in the United States was enacted in New York in 1984. Over the next few years, most states enacted belt use laws, and by 1991 ~~-eight states and the District of Columbia required safety belt use. Belt use in the United States was very low - 15% or less - before the This work was supported by the Insurance Institute for Highway Safety. Allan F. Williams is Vice President for Research with the InsuranceInstitute for Highway Safety; he holds a Ph.D. in Social Psychology from Harvard University, Dr. Willis has published more than 100 scientific papers in a wide variety of research areas including alcohol, drugs and driving; seat belt use; and preventing motor vehicle deaths and injuries among teenagers and children. He has investigated the roles of driver education, licensure age, and restraintuse in motor vehicle crashes. JoAnn K. We& is Research Associate with the kIsuIZXe Institute for Highway Safety; she holds a B.S. from Emmanuel College. Ms. Wells has published several articles concerning various aspects of seat belt and child restraint use, including seat belt use by teenagers and use of automatic seat belts. Her research interests also include innovative methods and programs to reduce alcoholimpaireddriving. Fall 1992/V&me 23/Mmber 3
state laws were enacted (Perkins, Cynecki, & Goryl, 1984). The laws have typically resulted in substantial increases in use rates and reductions in occupant deaths (Skinner & Hoxie, 1988; Campbell, Stewart, & Campbell, 1987; Lund, Zador, & Pollner, 1987). Al~ough belt use has not approached the 80-9096 use rates achieved in some countries, belt use is now at 40-50% in many states with laws and some have use rates over 60% (NHTSA, 1990a). States with primary enforcement laws, which allow motorists to be stopped and ticketed for a belt use violation, generally have higher use rates than states with secondary laws, which require a motorist to first be stopped for some other traffic offense (Campbell, 1987). As belt use has increased in states with laws, it has also increased somewhat in states without laws; however, it is generally lowest in states without laws. The best evidence for trends in belt use comes from the ongoing 19city survey conducted for the National Highway Traffic Safety Administration (NHTSA). In the four cities without belt use laws throughout the 1985-1990 period (Birmingham, FargolMoorhead, Phoenix, and 147
Providence), driver belt use increased from 17% to 36%. Driver belt use was 54% in the 14 cities with laws and 36% in the five cities without laws in the 1990 19-city survey (NHTSA, 1990b). Many states conduct their own safety belt use surveys, using a variety of methods. New Hampshire, a state without a belt use law, has been conducting statewide surveys since 1984, based on guidelines established by the NHTSA in 1983 (Phillips, 1983, May; NHTSA, 199Oc). According to these surveys, driver belt use increased from 16% in 1984 to 52% in 1990 (State of New Hampshire Highway Safety Agency, 1990, October). In the 10 counties in New Hampshire, reported belt use ranged narrowly in 1990 from 48% to 54%. Reported belt use was about the same on highways (53%) as on local roads (51%), and about the same in urban (53%) as in rural areas (51%). Safety belts were reported to be used by 55% of the 466 right-front passengers observed. These results are higher than typically reported for nonlaw states. The New England region includes 4 of the 10 states without safety belt use laws. The only New England state with a belt use law at the time of this survey was Connecticut;* driver belt use in Connecticut in 1990 was reported to be 59% (Connecticut Department of Transportation, 1988, January). Belt use for 1990 in Vermont was reported to be 39% (Vermont S.E.A.T. Coalition, 1990) and in Massachusetts it was reported to be 29% (Hingson, 1990). In the NHTSA 19-city survey, use in Boston was 33% in 1990. In the last survey undertaken in Maine in 1986, belt use was 23% (Hungerford, Kovenock, & Sorg. 1986). Rhode Island has not had a recent statewide survey, but in the 19-city survey, conducted in 1990 while Rhode Island did not have a law, use in Providence was 27% (NHTSA, 1990b). In comparison to the experience in these four nonlaw states, the belt use rate reported for New Hampshire is quite high. It is uncommon for belt use to be higher in jurisdictions without belt use laws than in those with laws. In the 19-city survey, Phoenix (without a law)
*Rhode Island passed a seat belt use law effective June 1991. 148
had a higher use rate in 1990 than five of the 14 cities surveyed in which belt use was required. However, none of the other four cities without laws had a use rate as high as the lowest rate among the 14 cities with laws. Belt use rates are influenced by factors other than mandatory use laws. For example, use is strongly correlated with socioeconomic status (Lund, 1986). However, New Hampshire is not markedly different from its neighboring New England states in terms of socioeconomic factors (Bureau of the Census, 1990). The coordinator of the New Hampshire Highway Safety Agency attributes the state’s reported high rate achieved without a law to safety belt education and the “basic common sense and intelligence” of New Hampshire motorists, and he says that they intend to increase belt use further using an educational approach (State of New Hampshire, 1990, October). Other New England states have provided safety belt education as well, but New Hampshire’s reported results are anomalous within the geographic region. In an attempt to verify these results, belt use surveys were conducted in four New Hampshire cities in the Spring of 1991. METHODS
Shoulder belt use by drivers and right front passengers was observed in four New Hampshire cities in the southeastern part of the state in May 1991. Nashua (population 81,000) and Manchester (population 102,800) are in Hillsboro County; Concord (population 35,800) is in Merrimack County; Rochester (population 24,700) is in Strafford County. Observations were made at 36 sites: 12 each in Nashua and Manchester and six each in Concord and Rochester. Sites were at intersections with traffic lights, stop signs, or yield signs, and high volumes of traffic. Data were collected once at a site either at morning rush hour (7:00-9:00 a.m.), evening rush hour (4:00-6:30 p.m.), or midday (1l:OO a.m.-l :30 p.m.). Observers were located on the side of the observed vehicle opposite the driver and observed and recorded shoulder belt use of drivers and right-front passengers as vehicles slowed or stopped at the traffic signal. Shoulder belt use Journal of Safety Research
Rochester roads as in the New Hampshire state survey (23%) compares to the 51% driver belt use rate for &afford County reported in the New Hampshire state survey.
was indicated only if the belt was correctly positioned and fastened. For example, if the belt was merely draped over the shoulder and unfastened, or fastened behind the back or under the arm, it was coded as shoulder belt not used. Passenger cars, vans, pickups, and utility vehicles with New Hampshire license plates were observed, as in the New Hampshire statewide survey.
DISCUSSION The survey conducted in 1990 by the state of New Hampshire reported a statewide belt use rate of 528, with belt use showing very little variation by county or by type of road or type of locale. In contrast, the present survey conducted at 36 sites in four southeastern New Hampshire cities, found a driver belt use rate of 36%. Belt use was 50% or greater at only three of the 36 sites and at one of the 11 sites common to both surveys. Both surveys included the same types of vehicles and types of sites. Subsequent to completion of the present study, New H~pshire officials provided the authors with further details on their observation techniques and demonstrated these techniques. The state survey counted occupants as restrained if they were using belts incorrectly (e.g., under the arm), whereas in this study such occupants were classified as unrestrained because no protection was being provided. This different procedure would account for a small part of the difference in belt use rates. The main reason for the higher use rates found by New Hampshire’s survey appears to be that in the state survey an attempt was made to observe all passing vehicles. In most
RESULTS Safety belt use observations were made on 25,003 drivers and 5,930 right-front passengers in the four cities. Table 1 indicates that driver belt use rates ranged from 28% in Rochester to 45% in Concord and was 36% overall. Passenger belt use rates were slightly lower, 33% overall. Driver belt use rates at all 36 sites ranged from 20% to 59%. At only three sites was use 50% or higher. Driver belt use in Manchester (35%) and Nashua (37%) compares to a driver belt use rate of 52% in Hillsboro County reported in the New Hampshire state survey. At Manchester and Nashua sites in the present survey located on the same roads (though not necessarily at the same intersections) as in the New Hampshire state survey, belt use was 33%. In the present survey, driver belt use was 45% in Concord and 48% on the same roads as those used in the New H~psh~e state survey in Merrimac County, where use was reported at 52%. In the present survey, driver belt use in Rochester (28%) and on the same
TABLE 1 PERCENT SHOULDER BELT USE IN tiEW HAMPSHIRE, MAY 1991
Dlk.9fS
Number C&
CG%SXd
Rlpht-Ftont
Total
Possen~~tr
ot
stes
Peccent
(W
Percent
6
45
(4.274)
(Nf
PerCMM
39
(393)
44
(5.213)
(1.973)
3s
(10.437)
(NO
h4anchedel
12
33
w-4>
36
Nashua
12
37
(7.776)
32
(1.5m
35
(9.436)
Rochester
4
28
(4.469)
26
(1 .W)
28
(5‘847)
36
36
(25.003)
33
(5.930)
36
(30.933)
AH Cillss
Foil 199.2hbIume 23/iVumber 3
cases, shoulder belt use will be easily and quickly apparent even in fast-moving vehicles and thus vehicles with belt users will tend to be included in the survey. However, confinning the absence of belt use tends to take more time, and in a stream of moving vehicles there will be more cases in which the observer is uncertain as to belt use. The techniques used by the state officials call for skipping vehicles where there is uncertainty. These procedures are thus likely to provide an overestimate of the true use rate. In contrast, only cars that are slowed or stopped at traffic lights or stop signs were observed for this study, so that use or nonuse could be clearly established in each car viewed. The authors also observed belt use at two sites in Nashua and two sites in Rochester at the exact locations as in the state survey, subsequent to the present study, and found belt use rates of 20-30%, whereas in the state survey use rates were reported to be 40-50% at these sites. In most states, including New Hampshire, belt use observation techniques are based on guidelines provided by the NHTSA. It is suggested that these guidelines be made more explicit to ensure that accurate use rates are obtained and that observation techniques are applied consistently across states. The present results suggest that New Hampshire has use rates typical of a state without a belt use law. Presumably, enactment of a belt use law would, as in other states, increase use considerably. The National Highway Traffic Safety Administration has set a national goal of 70% belt use by 1992. A key component of the program is to publicize and enforce safety belt use laws. Studies here and abroad have repeatedly shown that the combination of publicity and law enforcement are necessary to raise safety belt use rates to high levels. The use of educational approaches alone, as advocated by some New Hampshire officials, has been tried throughout the world, but evaluations consistently show that such programs do not work. Clearly, meeting the NHTSA goal without a mandatory use law will be problematic for states such as New Hampshire.
150
REFERENCES Bureau of the Census. (1990). Statistical abstract of the United States 1990. Washington, DC: U.S. Government Printing office. Campbell, B. J. (1987). The relationship of seat belt law enforcement to level of belt use (HSRC-TR72). Chapel Hill, NC: University of North Carolina Highway __. Safety Research Center. Campbell, B. J., Stewart, J. R., & Campbell, F. A. (1987). 1985-1986 experience with belt laws in the United States. Chanel Hill. NC: Universitv of North Carolina
Highway Safety Research Center. _ Connecticut Department of Transportation, Office of Highway Safety. (1988, January). Safety belt law: O&pant protection program. Wethersfieid Cfz Author. Hingson, R. (1990). Comments on safety belt use, occupant injury and public attitudes about safety belts and‘belt laws in Massachusetts (Memorandum to Governor’s
Highway Safety Bureau Occupant Protection Program Evaluation). Boston, MA. Hungerford, D., Kovenock, D., & Sorg, J. (1986). Maine seat belt use observation study. Grono, ME: Northeast Research. Lund, A. K. (1986). Voluntary seat belt use among U.S. drivers: Geographic, socioeconomic, demographic variation. Accident Analysis and Prevention, 18, i3-50. Lund, A. K., Zador, P., & Palmer, J. (1987). Motor vehicle occupant fatalities in four states with seat belt use laws. SAE 870224. Warrendale, PA: Society of Automotive
Engineers. National Highway Traffic Safety Administration (NHTSA). (1990a). Observed safety belt use statistics by state. Washington, DC: Author. National Highway Traffic Safety Administration (NHTSA). (1990b). Use of automatic safety belt systems in 19 cities. Washington, DC: Author. National Highway Traffic Safety Administration (NHTSA). (199Oc).Belt use guidelines. Washington, DC: U.S. Dept. of Transportation. Perkins, D. D., Cynecki, M. J., & Goryl, M. E. (1984). Restraint system usage in the traffic population (DGT HS 806 582). Washington, DC: U.S. Department of Transportation, National Highway Traffic Safety Administration. Phillips. B. M. (1983, May). Restraint system usage in traffic oomdation CDoT HS 806-424). Washington, DC U.S. Department of Transportation, .NationalHighway Traffic Safety Administration. Skinner, D., & Hoxie, P (1988). Effects of seat belt laws on highway fatalities: Update - April 1988. (Project Memorandum DOT-TSC-HS870-PM-88-5). Washington, DC: National Highway Traffic Safety Administration. State of New Hampshire. (1990, October). Press release accompanying
statewide
seat belt survey results.
Concord, NH: Highway Safety Agency. State of New Hampshire Highway Safety Agency. (1990, October). I990 safetv belt survev. Concord, NH: Highway’Safety Agency. Vermont S.E.A.T. Coalition. (1990). Safety belt use in Vermont: Observational study. Burlington, VT: Vermont S.E.A.T. Coalition.
Journal of Safety Research