Approximately 2.38 million janitors are employed in the U.S. While high physical workload may explain a lost-work days rate 2.7 times greater than other occupations, little is known about the association between janitors’ physical workload, mental workload, and stress.
OBJECTIVE:
The objective of this study was to assess the associations between physical (ergonomic) and mental workload exposures and stress outcomes among janitors.
METHODS:
Questionnaire data, focused on ergonomic workload, mental workload and stress, were collected from Minnesota janitors for a one-year period. Physical workload was assessed with Borg Scales and Rapid Entire Body Assessments (REBA). Mental workload assessment utilized the NASA Task Load Index (TLX). Stress assessments utilized single-item ordinal stress scale (SISS) and Perceived Stress Scale-4 (PSS-4) measures. Descriptive and multivariable analyses, including bias adjustment, were conducted.
RESULTS:
Odds ratios (OR) and 95% confidence intervals (CI) for ergonomic workload (task frequency) effects on SISS were: REBA (1.18 OR, 1.02–1.37 CI); Borg (1.25 OR, 1.00–1.56 CI); combined REBA and Borg (1.10 OR, 1.01–1.20 CI). Mental workload was associated with higher PSS-4 levels (0.15 Mean Difference, 0.08–0.22 CI) and a 3% increased risk for each one-unit increase in the SISS scale (1.03 OR, 1.02–1.05 CI).
CONCLUSIONS:
This research demonstrated a moderate effect of physical and mental workloads on stress among janitors.
CharlesLE, LoomisD, DemissieZ. Occupational hazards experienced by cleaning workers and janitors: A review of the epidemiologic literature. Work. 2009;34:105–16.
3.
BLS. Nonfatal Occupational Injuries and Illnesses Requiring Days Away From Work. Economic News Release. https://www.bls.gov/news.release/osh2.htm (2016, accessed 13 June 2018).
4.
IrieM, AsamiS, NagataS, et al.Relationships between perceived workload, stress and oxidative DNA damage. Int Arch Occup Environ Health. 2001;74:153–7.
5.
StotlandE, PendletonM. Workload, Stress, and Strain among Police Officers. Behav Med. 1989;15:5–17.
6.
AaråsA, HorgenG, BjørsetH-H, et al.Musculoskeletal, visual and psychosocial stress in VDU operators before and after multidisciplinary ergonomic interventions. Appl Ergon. 1998;29:335–54.
7.
FrankenhaeuserM. The psychophysiology of workload, stress, and health: Comparison between the sexes. Ann Behav Med. 1991;13(4):197–204.
8.
RossJ, ClaypooleV, SzalmaJ. Social Facilitation and Its Effects on the Workload and Stress of a Vigilance Task. Hum Factors Appl Psychol Student Conference. https://commons.erau.edu/hfap/hfap-2016/posters/39 (2016, accessed 27 December 2017).
9.
WilliamsDR, Yan YuY, JacksonJS, et al.Racial Differences in Physical and Mental Health. J Health Psychol. 1997;2:335–51.
10.
CiarrochiJ, DeaneFP, AndersonS. Emotional intelligence moderates the relationship between stress and mental health. Pers Individ Dif. 2002;32:197–209.
11.
PearlinLI, SchiemanS, FazioEM, et al.Stress, Health, and the Life Course: Some Conceptual Perspectives. J Health Soc Behav. 2005;46:205–19.
12.
SeixasN, StoverB, SimcoxN, et al.Work Intensity, Injury, Stress and Pain among Commercial Janitors. Occup Env Med. 2014;71:A4–A4.
13.
LandsbergisPA, CahillJ. Labor union programs to reduce or prevent occupational stress in the United States. Int J Health Serv. 1994;24(1):105–29. DOI: 10.2190/501D-4E1P-260K-2500.
14.
JahnckeH, HyggeS, MathiassenSE, et al.Variation at work: alternations between physically and mentally demanding tasks in blue-collar occupations. Ergonomics. 2017;60:1218–27.
15.
MetzgerU, ParasuramanR. Automation in Future Air Traffic Management: Effects of Decision Aid Reliability on Controller Performance and Mental Workload. 36. http://journals.sagepub.com/doi/pdf/10.1518/0018720053653802 (2005, accessed 17 May 2018).
16.
YurkoYY, ScerboMW, PrabhuAS, et al.Higher Mental Workload is Associated With Poorer Laparoscopic Performance as Measured by the NASA-TLX Tool. Simul Healthc J Soc Simul Healthc. 2010;5:267–71.
17.
Readable.io.Measure the Readability of Text – Text Analysis Tools, https://readable.io/text/ (2018, accessed 9 March 2018).
18.
CoyleA. Comparison of the Rapid Entire Body Assessment and the New Zealand Manual Handling ‘Hazard Control Record’, for assessment of manual handling hazards in the supermarket industry. Work. 2005;385–96.
NobleBJ. Clinical applications of perceived exertion. Med Sci Sports Exerc. 1982;14:406–11.
23.
StetsonBA, RahnJM, DubbertPM, et al.Prospective evaluation of the effects of stress on exercise adherence in community-residing women. Heal Psychol. 1997;16:515–20.
24.
DasB, GangopadhyayS. Prevalence of Musculoskeletal Disorders and Physiological Stress Among Adult, Male Potato Cultivators of West Bengal, India. Asia Pacific J Public Heal. 2015;27:NP1669–NP1682.
25.
ChoiS-Y, ImS-J, LeeY-H, et al.The Effects of Hospital Worker’s Job Stress and Work Posture Risk on the Muscular Skeletal Disease related Consciousness Symptom –With Emphasis on Path Analysis Model. J Korea Saf Manag Sci. 2009;11:57–67.
NicolayCW, WalkerAL. Grip strength and endurance: Influences of anthropometric variation, hand dominance, and gender. Int J Ind Ergon. 2005;35:605–18.
28.
BuchholzB, PaquetV, PunnettL, et al.PATH: A work sampling-based approach to ergonomic job analysis for construction and other non-repetitive work. Appl Ergon. 1996;27:177–87.
29.
International Sanitary Supply Association I. 612 Cleaning Times and Tasks. 2014.
30.
HartSG. Nasa-Task Load Index (NASA-TLX); 20 Years Later. Proc Hum Factors Ergon Soc Annu Meet. 2006;50:904–908.
CaoA, ChintamaniKK, PandyaAK, et al.NASA TLX: Software for assessing subjective mental workload. Behav Res Methods. 2009;41:113–117.
33.
ParkPC. Comparison Of Subjective Mental Workload Assessment Techniques For The Evaluation Of In-Vehicle Navigation Systems Usability. Usability. Organizing Committee 5th World Congress, https://trid.trb.org/view/513825 (1998, accessed 20 March 2018).
34.
WilsonMR, PooltonJM, MalhotraN, et al.Development and Validation of a Surgical Workload Measure: The Surgery Task Load Index (SURG-TLX). World J Surg. 2011;35:1961–69.
35.
RutledgeT, StuckyE, DollarhideA, et al.A real-time assessment of work stress in physicians and nurses. Heal Psychol. 2009;28:194–200.
36.
TaverniersJ, TaylorMK, SmeetsT. Delayed memory effects after intense stress in Special Forces candidates: Exploring path processes between cortisol secretion and memory recall. Stress. 2013;16:311–320.
EloA. L., LeppänenA. & JahkolaA.. Validity of a single-item measure of stress symptoms. Scand J Work Environ Health. 2003;29.6:444–451.
39.
WarttigSL, ForshawMJ, SouthJ, et al.New, normative, English-sample data for the Short Form Perceived Stress Scale (PSS-4). J Health Psychol. 2013;18:1617–1628.
40.
FolkmanS. Stress: Appraisal and Coping. In: Encyclopedia of Behavioral Medicine. New York, NY: Springer New York, pp. 1913–1915.
41.
CohenS, KamarckT, MermelsteinR. A Global Measure of Perceived Stress. J Health Soc Behav. 1983;24:385.
42.
RamirezA, GrahamJ, RichardsM. et al.Mental health of hospital consultants: the effects of stress and satisfaction at work. Lancet. 1996;347:724–728.
43.
HarrisPA, TaylorR, ThielkeR, et al.Research electronic data capture (REDCap)—A metadata-driven methodology and workflow process for providing translational research informatics support. J Biomed Inform. 2009;42:377–381.
44.
HernanMA, Hernández-DíazS, WerlerMM, et al.Causal Knowledge as a Prerequisite for Confounding Evaluation: An Application to Birth Defects Epidemiology. Am J Epidemiol. 2002;155:176–184.
TextorJ, HardtJ, KnüppelS. DAGitty: A Graphical Tool for Analyzing Causal Diagrams. Epidemiology. 2011;22:745.
47.
HanleyJA, NegassaA, EdwardesMD deB. et alStatistical Analysis of Correlated Data Using Generalized Estimating Equations: An Orientation. Am J Epidemiol. 2003;157:364–375.
48.
HernánMA, RobinsJM. Estimating causal effects from epidemiological data. J Epidemiol Community Health. 2006;60:578–86.
49.
HorvitzDG, ThompsonDJ. A generalization of sampling without replacement from a finite universe. J Am Stat Assoc. 1952;47(260):663–85. DOI: 10.2307/2280784.
50.
LandisJR, KochGG. The Measurement of Observer Agreement for Categorical Data. Biometrics. 1977;33:159.
NawiNSM, NordinN. Assessment of oil palm fresh fruit bunches harvesters working postures using REBA. Adv Eng Forum. 2013;10:122–127.
53.
GentzlerM, StaderS. Posture stress on firefighters and emergency medical technicians (EMTs) associated with repetitive reaching, bending, lifting, and pulling tasks. Work. 2010;37:227–39.
54.
AnsariNA, SheikhMJ. Evaluation of work Posture by RULA and REBA: A Case Study. IOSR J Mech Civ Eng Ver III11:2320–34.
55.
JakobsenMD, SundstrupE, PerssonR, et al.Is Borg’s perceived exertion scale a useful indicator of muscular and cardiovascular load in blue-collar workers with lifting tasks? A cross-sectional workplace study. Eur J Appl Physiol. 2014;114:425–34.
ChenWQ, YuIT-S, WongTW. Impact of occupational stress and other psychosocial factors on musculoskeletal pain among Chinese offshore oil installation workers. Occup Environ Med. 2005;62:251–6.
58.
TempleJG, WarmJS, DemberWN, et al.The Effects of Signal Salience and Caffeine on Performance, Workload, and Stress in an Abbreviated Vigilance Task. Hum Factors J Hum Factors Ergon Soc. 2000;42:183–194.
59.
LipscombHJ, NolanJ, PattersonD, et al.Safety, incentives, and the reporting of work-related injuries among union carpenters: “You’re pretty much screwed if you get hurt at work”. Am J Ind Med. 2013;56:389–99.
60.
SchibalskiJ V, MüllerM, Ajdacic-GrossV, et al.Stigma-related stress, shame and avoidant coping reactions among members of the general population with elevated symptom levels. Compr Psychiatry. 2017;74:224–30.
GerberichS, ChurchT, McGovernP, et al.An epidemiological study of the magnitude and consequences of work related violence: the Minnesota Nurses’ Study. Occup Env Med. 2004;61:495–503.
64.
WeiC, GerberichSG, AlexanderBH, et al.Work-related violence against educators in Minnesota: Rates and risks based on hours exposed. J Safety Res. 2013;44:73–85.
65.
LevinKA. Study design III: Cross-sectional studies. Evid Based Dent. 2006;7:24–25.
