Need for recovery scale in the firefighting context: Examination of the Persian culture-adapted version

Abstract

BACKGROUND:

Work-related fatigue can cause disruption in mental and physical activities of the workers. Considering the importance of recovery from fatigue in emergency services, as seen in firefighting duties, the preparation and validation of the Need For Recovery Scale (NFRS) questionnaire can be useful and effective.

OBJECTIVE:

This study assessed the reliability and validity of the Persian version of Need For Recovery Scale among industrial firefighters.

METHODS:

Need for recovery scale contains 11 questions. First, a questionnaire was translated using backward-forward method. Then, for measuring validity of the questionnaire, the opinions of 10 experts in related fields were obtained. Content Validity Index (CVI) and Content Validity Ratio (CVR) were calculated. The reliability was determined through 107 questionnaires completed by the industrial firefighters.

RESULTS:

The average age of the firefighters in this study was 37.5 years and they had an average of 10 years of work experience. The mean Need For Recovery Index from fatigue was 33.03 for the study population. Of the first 11 questions, 9 questions in the original NFRS showed a satisfactory level of CVR. The Content Validity Index and Cronbach’s α were 0.89 and 0.77 respectively.

CONCLUSION:

Based on the results, the Need For Recovery Scale is a reliable tool for assessing fatigue and revealed an acceptable level of validity and reliability that makes it usable for fatigue assessment in the industrial firefighters.

Keywords

Occupational fatigue psychometric properties validity and reliability fireman fatigue questionnaire

1 Introduction

Fatigue is defined as an unwanted change in the psychophysiological control mechanism in the humankind [1]. This mechanism is responsible for regulating the occupational behaviors. Due to fatigue-induced disruption of the mental and physical capability, an operator cannot meet the demands of his/her job [1]. Among various types of fatigue, work-related fatigue is a serious growing issue that needs more attention [2]. Work-related fatigue has several negative physiological and mental consequences on workers’ health [2, 3]. This type of fatigue is one of the known consequences of unbalanced industrial and technological development. More than 40 percent of workforce in developed countries suffer work-related fatigue. In some other countries, this figure reaches up to 60 percent [2]. Work-related fatigue is reported by 2–2.5 million workers in the U.S.A [4]. Another study [5] showed that more than 40 percent of workers complained of work-related fatigue in Iran. Exposure to the occupational fatigue can lead to various disorders, including but not limited to sleep disorders, psychophysiological problems, low quality of life, absenteeism and reduced work ability [3]. In addition, fatigue can also deteriorate some critical safety-related aspects of workers’ abilities, including reaction time, risk perception and situation awareness [6, 7]. Dminished critical safety performance can endanger the emergency responders’ health and safety, while conducting their missions [8, 9]. The occupational fatigue in the emergency service providers, firemen for instance, has a much more importance since it can influence their cognitive and decision-making abilities as well as their physical performance [8 , 11]. In such situations, the firefighter’s ability for recovering from fatigue is a significant parameter that could impact the firefighters’ health [7 , 12]. Recovery is defined as the needed period to restore the situation(s) to the desired level of performance after stopping exposure to stressful condition(s) [1]. Sometimes recovery from fatigue is made during the resting time at workplace, while most of the time it starts after the end of a shift work and continues to the beginning of the next shift [3]. Assessing the recovery from fatigue in some occupations, in particular firefighters, can be considered as a remarkable topic. There are several methods to assess work-related fatigue [1]. One of the most commonly accepted methods for assessing the need for recovery is the Need For Recovery Scale (NFRS). The concept of need for recovery was proposed by the Meijman’s in the Effort-Recovery Model. According to this model, depending on efforts made by (the) operator and the imposed workload, a specified work period is required to recover from fatigue. This interval is necessary to return to the good state just before starting the assigned tasks [13]. The NFRS was designed to evaluate short-term consequences of the work-related fatigue, including workload pressure, lowered professional performance and lack of energy to perform tasks [14]. This scale is a powerful predictor of fatigue. An imbalanced NFRS could be considered as a warning signal of probable failure in personal performance, safety, well-being and health [2, 13]. In addition, NFRS quantifies the extent of the operator’s efforts and the imposed workload and derives the operator’s state of health, based on this comparison [15]. Moriguchi et al. [3], analyzed the reliability of the NFRS for industrial environments. Another study [1] declared the appropriate reliablity for the NFRS. NFRS has a good sensitivity for various conditions. Considering the importance of the occupational fatigue concept among firefighters and unique characteristics of the NFRS, the present study aimed to assess its validity and reliability for industrial firefighting context.

2 Materials and methods

This descriptive, analytical and cross-sectional study was conducted to develop the Persian version of the NFRS among Iranian industrial firefighters.

All of available firefighters in an industrial park were participated in the study. 114 firemen were included in the present study, while 107 cases completed the requested questionnaire. The firefighters were full-time, shift workers and not volunteer. Content validity and Cronbach’s α were used to assess validity and reliability of the questionnaire (Fig. 1) The research ethics committee of Hamadan university of medical sciences gave statements regarding the used plan in this study and approved all the procedures.

2.1 Need for recovery questionnaire

The NFRS was used for evaluation of workload, occupational fatigue and the required amount of the rest time [12]. This questionnaire consisted of 11 questions with yes/no answers. For each question a total score of 9.09 is attainable, thus the overall score range varies between 0 to 100. Giving more than four positive answers (e.g, The overall score of 45.45 and more) indicates high workload and needs to recovery for the interviewee [1].

2.2 The experts panel assignment

The experts panel was composed of ten qualified firefighters (domain experts) and some academic specialists (Human factors specialists, Occupational Health Masters and Epidemiologists with expertise in the qouestionnaire-based studies). First, the original version of the NFRS was translated to the Persian. After that, the translated questionnaire was back-translated to its original language by two natives. Then, the translated content was reviewed for correspondence with the original version. After coordination with the questionnaire developer, some minor amendments were implemented and the questionnaire was finalized.

2.3 Evaluation of the questionnaire validity

The Lawshi’s method for analysis of Content Validity Ratio (CVR) was used in the present study. The prepared questionnaires were distributed among the experts. The responses were divided into three categories as follows; “necessary”, “useful, but unnecessary” and “unnecessary”. The CVR was calculated based on the completed questionnaires: $CVR = \frac{ne - \frac{N}{2}}{\frac{N}{2}}$

ne: number of persons responding to requested questions

N: total number of experts

After determining the CVR, the Content Validity Index (CVI) and Scale-level Content Validity Index/ Averaging Calculation Method (S-CVI/AVE) were calculated to ensure that the best questions were selected for the questionnaire.

CVI simplicity, relevancy and clarity were scored by the experts in a Likert scale.

Simplicity, relevancy and clarity were considered by the experts separately to be scored for evaluating the CVI in a Likert scale. Finally, the CVI score for each item was determined by adding the agreed highest score (3 and 4) divided into the number of the experts. Hyrkas et al, recommended the score of 0.79 as a cut-off point for accepting items based on the CVI score. The scores between 0.70 and 0.79 require correction and the scores below 0.7 should be removed. In the next phase, the S-CVI/AVE was calculated for each question based on the CVI scores.

2.4 Evaluation of the questionnaire reliability

Determining the Cronbach’s α is an accepted method for evaluating the reliability and internal consistency of the Likert-based questionnaires [16]. This method was used in the present study to verify the reliability of the proposed questionnaire. The α should be at least 0.7 to remain in the assessment tool. The obtained score of 0.7 indicates a 70% stability for the calculated scores of the proposed tool (questionnaire). The measure of the Cronbach’s α is equal to the reliability coefficient of all questions after splitting into two same sections. The α greater than 0.9 is considered as excellent, up to 0.8 is good, up to 0.7 is acceptable, 0.6–0.7 is arguable, 0.5–60.6 is week and less than 0.5 is considered as unacceptable. After importing the obtained data into the SPSS version 23.0, the Cronbach’s α was determined.

3 Results

The results revealed that the measure of the CVR and CVI were higher than the accepted cut-off points for all questions, except two. Questions 1 and 4 were omitted from the queries because of not meeting the cut-off point. In the present study, CVR and CVI were 0.85 and 0.89, respectively. Tables 1 and 2, shows the CVR and CVI for collected data. The findings showed an acceptable reliability and validity for the proposed tool. In addition, the Cronbach’s α was 0.77 that demonstrated an acceptable measure. The Persian questionnaire is included in the appendix.

Table 1
Question items and result of CVI for firefighters

Question

1 I find it difficult to relax at the end of a working day.^*

2 By the end of the working day, I feel worn out.^

3 Because of my job, at the end of the working day I feel rather exhausted.^

4 After the evening meal, I generally feel in good shape.^*

5 I general, I only start to feel relaxed on the second nonworking day.^

6 I find it difficult to concentrate in my free time after work.^

7 I cannot really show any interest in other people when I have just come home myself.^

8 Generally, I need more than an hour before I feel completely recuperated after work.^

9 When I get home from work, I need to be left in peace for a while.^

10 Often, after a day’s work I feel so tired that I cannot get involved in other activities.^

11 A feeling of tiredness prevents me from doing my work as well as normally would during the last part of the working day.^**

Question
1	I find it difficult to relax at the end of a working day.^*
2	By the end of the working day, I feel worn out.^**
3	Because of my job, at the end of the working day I feel rather exhausted.^**
4	After the evening meal, I generally feel in good shape.^*
5	I general, I only start to feel relaxed on the second nonworking day.^**
6	I find it difficult to concentrate in my free time after work.^**
7	I cannot really show any interest in other people when I have just come home myself.^**
8	Generally, I need more than an hour before I feel completely recuperated after work.^**
9	When I get home from work, I need to be left in peace for a while.^**
10	Often, after a day’s work I feel so tired that I cannot get involved in other activities.^**
11	A feeling of tiredness prevents me from doing my work as well as normally would during the last part of the working day.^**

^*Reject if Content Validity Index (CVI) < 0/70, ^**Accept if Content Validity Index (CVI) ≥0/70.

Table 2

Question items and result of CVR for firefighters

Question
1	I find it difficult to relax at the end a working day.^*
2	By the end of the working day, I feel worn out.^**
3	Because of my job, at the end of the working day I feel rather exhausted.^**
4	After the evening meal, I generally feel in good shape.^*
5	I general, I only start to feel relaxed on the second nonworking day.^**
6	I find it difficult to concentrate in my free time after work.^**
7	I cannot really show any interest in other people when I have just come home myself.^**
8	Generally, I need more than an hour before I feel completely recuperated after work.^**
9	When I get home from work, I need to be left in peace for a while.^**
10	Often, after a day’s work I feel so tired that I cannot get involved in other activities.^**
11	A feeling of tiredness prevents me from doing my work as well as normally would during the last part of the working day.^**

^*Reject if Content Validity Ratio (CVR) < 0/62, ^**Accept if Content Validity Ratio (CVR) ≥0/62.

4 Discussion

This study was conducted as a cultural adaptation of the Persian version of the Need for Recovery Scale among industrial firefighters. Work-related fatigue is a multifactorial concept and has been quantified through a variety of methods [17]. One of the most recent approaches for quantifing fatigue in workplaces is using of “need for recovery” theory [18]. Based on this theory, recovery from work refers to the physical and mental process by which workers recover from their fatigue and stress and renew their power which were lost during working [19]. In occupational context, especially firefighting, recovery from stress is pivotal to employees’ well-being and quality of working life [20].

Occupational fatigue can be prevented through providing an acceptable level of workload and rest schedule [21]. One of the most common instrument for quantifiying need for recovery and occupational fatigue is “NFRS: Need for Recovery Scale”. Some studies reported the psychometric properties of NFRS in some occupations and countries [3, 12]. In the present study, NFRS was applied for a novel occupational group – industrial firefighters – which has not been studied yet.

The results showed a good validity and reliability for the NFRS among industrial firefighters. The Cronbach’s α was estimated at 0.77 that is considered as a good reliability measure. In a recent study, Stevens et al, studied short version of the Danish need for recovery scale against the full scale and concluded that, the short-form NFR scale, consisting of three questions from the original Scale, seems to be an appropriate substitute for the full version of the questionnaire [22].

Moriguchi et al. [3] reported Cronbach’s α of 0.87 for the Brazilian version of the NFRS. Samadi et al. [12] reported a good validity for the NFRS among Iranian miners. They reported Cronbach’s α of 0.82 for the proposed questionnaire. In another study, Veldhoven et al. [1] reported Cronbach’s α of 0.88 for their study. Croon et al. [23] reviewed the NFRS among nurses and reported 0.67, 0.72 and 0.80 for ICC (Interclass Correlation Coefficient) over the three time intervals. Various studies [1, 24] have reported acceptable levels of quality for the NFRS. Others reported that CVRs are acceptable as well. A clinical study of patients showed the correlation of 0.60 between the NFRS and other fatigue-related measures [24]. Moreover, a substantial relationship was reported between occupational stress and the need for recovery scale [1]. In comparison with other fatigue assessment tools, it could be concluded that NFRS is reliable to predict the occupational fatigue at the initial stage of exposure [3]. The strength of the present study is the application of the effort-recovery model and NFRS questionnaire among firefighters. Despite of the consistency of obtained results with Giuliani et al.’s findings [20], the present study addressed only the industrial firefighters. It might be recommended to conduct a similar study for civil or municipal firefighting teams.

5 Conclusion

Our results provide further support for the applicability of NFRS for quantifing occupational fatigue. The Persian version of the NFRS is a valid and reliable tool for measuring occupational fatigue among industrial firefighters. This developed version can be useful for further studies.

Footnotes

Acknowledgments

The authors wish to thank the firefighter of Iran’s Petrochemical special economic zone. The authors also wish to thank Saeedeh Mosaferchi for her comments and Mojtaba Ahmadi for carrying out critical review of this paper.

Conflict of interest

No potential conflict of interest was reported.

Funding

This study was supported by Hamedan University of Medical Sciences [grant number IR.UMSHA.REC.1396.800].

References

Van Veldhoven

, Broersen

. Measurement quality and validity of the “need for recovery scale”. Occupational and Environmental Medicine. 2003;60(suppl 1):i3–i9.

van der Starre

, Coffeng

, Hendriksen

, van Mechelen

, Boot

. Associations between overweight, obesity, health measures and need for recovery in office employees: a cross-sectional analysis. BMC Public Health. 2013;13(1):1207.

Moriguchi

, Alem

MER

, Veldhoven

, Coury

HJCG

. Cultural adaptation and psychometric properties of Brazilian Need for Recovery Scale. Revista de saude Publica. 2010;44(1):131–9.

Ford

, Anne

, Johnson

. Oslersweb: inside the habyrinth o the chronic fatigue syndrome epidemic New York. Crown publishers; 1996.

Rezaei

, Baghianimoghadam

, Halvani

. Fatigue situation in tile industries workers. Salāmat-i kār-i Īrān. 2007;4(3):57–63.

Smith

, DeJoy

, Dyal

M-A

, Huang

. Impact of work pressure,work stress andwork–family conflict on firefighter burnout. Archives of Environmental & Occupational Health. 2017:1-8.

McGillis

. The sleep behaviour and fatigue trends of wildland firefighters during non-fire and fire deployments: Laurentian University of Sudbury; 2017.

Useche

, Ortiz

, Cendales

. Stress-related psychosocial factors at work, fatigue, and risky driving behavior in bus rapid transport (BRT) drivers. Accident Analysis & Prevention. 2017;104:106–14.

Gumieniak

, Poulin

, Gledhill

, Jamnik

. Examining wildland fire fighter candidate pass rates over five years post-implementation on a newly-developed physical employment standard. Work. 2019(Preprint):1-9.

10.

Kalatpour

, Saeidnia

, Babamiri

, Soltanian

. The Impact of Individual Variables on perceived effort-reward imbalance and fatigue need for recovery in industrial firefighters. Journal of Occupational Hygiene Engineering. 1-9.

11.

Lane

, Hardwick

, Janus

, Chen

, Lu

, Mayer

. Comparison of the firefighter candidate physical ability test to weight lifting exercises using electromyography. Work. 2019;62(3):459–67.

12.

Samadi

, Kalantari

, Mostafavi

, Zanjirani fFarahani

, Bakhshi

. Using the Need for Recovery Scale to Assess Workload in Mine Workers and Its Relationship With Demographics. Journal of Ergonomics. 2017;4(4):1–7.

13.

de Croon

, Sluiter

, Frings-Dresen

. Need for recovery after work predicts sickness absence: a 2-year prospective cohort study in truck drivers. Journal of Psychosomatic Research. 2003;55(4):331–9.

14.

Jansen

, Kant

, van Amelsvoort

, Nijhuis

, van den Brandt

. Need for recovery from work: evaluating short-term effects of working hours, patterns and schedules. Ergonomics. 2003;46(7):664–80.

15.

Smolders

, de Kort

, Tenner

, Kaiser

. Need for recovery in offices: Behavior-based assessment. Journal of Environmental Psychology. 2012;32(2):126–34.

16.

Ghamari

, Mohammadbeigi

, Mohammadsalehi

, Hashiani

. Internet addiction and modeling its risk factors in medical students, Iran. Indian Journal of Psychological Medicine. 2011;33(2):158.

17.

Andrei

, Griffin

, Grech

, Neal

. How demands and resources impact chronic fatigue in the maritime industry. The mediating effect of acute fatigue, sleep quality and recovery. Safety Science. 2020;121:362–72.

18.

Wentz

, Gyllensten

, Sluiter

, Hagberg

. Need for recovery in relation to effort from work and health in four occupations. International Archives of Occupational and Environmental Health. 2020;93(2):243–59.

19.

Mache

, Servaty

, Harth

. Flexible work arrangements in open workspaces and relations to occupational stress, need for recovery and psychological detachment from work. Journal of Occupational Medicine and Toxicology. 2020;15(1):5.

20.

Giuliani

, Gerstner

, Mota

, Ryan

. Influence of Demographic Characteristics and Muscle Strength on the Occupational Fatigue Exhaustion Recovery Scale in Career Firefighters. Journal of Occupational and Environmental Medicine. 2020;62(3):223–6.

21.

van Dam

, Noordzij

, Born

. Social workers and recovery from stress. Journal of Social Work. 2020: 1468017320911350.

22.

Stevens

, Crowley

, Garde

, Mortensen

, Nygård

C-H

, Holtermann

. Validation of a Short-Form Version of the Danish Need for Recovery Scale against the Full Scale. International Journal of Environmental Research and Public Health. 2019;16(13):2334.

23.

De Croon

, Sluiter

, Frings-Dresen

. Psychometric properties of the Need for Recovery after work scale: test-retest reliability and sensitivity to detect change. Occupational and Environmental Medicine. 2006;63(3):202–6.

24.

Jansen

, Kant

, van den Brandt

. Need for recovery in the working population: description and associations with fatigue and psychological distress. International Journal of Behavioral Medicine. 2002;9(4):322.