This study aimed to examine the associations among forward head posture (FHP), physical activity (PA) level, and neck function indicators in undergraduate and graduate students.

METHODS

A total of 102 undergraduate and graduate students were included. PA level was assessed using the International Physical Activity Questionnaire-Short Form. Cervical sagittal alignment was evaluated using the craniovertebral angle (CVA), and neck function indicators included cervical range of motion (ROM), joint position error (JPE), neck muscle strength, and neck muscle endurance.

RESULTS

Between-group comparisons indicated that the PA-sufficient group exhibited significantly greater CVA, neck flexor strength (NFS), neck extensor strength (NES), and neck flexor endurance (NFE) than the PA-insufficient group. Correlation analysis showed that CVA was significantly associated with PA level, cervical ROM, and JPE. Stepwise regression analysis indicated that cervical flexion and extension ROM, as well as JPE during extension and left and right rotation, were significantly associated with CVA.

CONCLUSIONS

These findings suggest that physical activity level may be associated with cervical alignment and neck muscle function in this population. In addition, cervical range of motion and joint position error may represent relevant functional characteristics related to forward head posture and should be considered in its evaluation.

Keywords: FHP; Physical activity; Cervical range of motion; Joint position sense; Neck strength and endurance

INTRODUCTION

The expansion of digital learning environments, coupled with increasingly sedentary lifestyles, has placed university students at an elevated risk of spinal alignment abnormalities. Among these, forward head posture (FHP) is one of the most prevalent postural deviations in this population [1], with a reported prevalence of 64-84% [2-4]. FHP is typically defined as a craniovertebral angle (CVA) of less than 50° [5]. This anterior displacement of the head increases the moment load on the cervical spine, thereby elevating musculoskeletal strain and potentially contributing to pain and functional impairment over time.

FHP is associated not only with morphological changes in alignment but also with functional alterations. A reduced CVA has been associated with decreased cervical range of motion (ROM) [6-8], and individuals with FHP have been reported to exhibit greater joint position error (JPE) [9-11]. Changes in muscle function have also been identified, including altered activation of the upper and lower trapezius muscles [12,13], imbalances in the flexion-extension strength ratio, reduced muscle strength [14,15], and decreased extensor endurance [16]. These findings suggest that FHP is not attributable to a single factor but rather represents a complex functional condition associated with broader alterations in neuromuscular and sensorimotor function. Furthermore, these deficits may impair the ability to maintain cervical alignment, thereby contributing to the persistence or progression of anterior head displacement [6-16].

These functional changes are not limited to structural alignment abnormalities but may also be influenced by lifestyle-related factors. Among these, physical activity (PA) is considered to play a key role in the maintenance and regulation of neuromuscular function, including muscle strength, joint mobility, and proprioception, all of which are associated with FHP. Insufficient PA may contribute to declines in functional components required to maintain postural alignment [17,18], and meta-analytic evidence indicates that PA level is significantly and positively associated with musculoskeletal function and muscle strength [19]. However, approximately 40-50% of university students have been reported not to meet the World Health Organization (WHO) recommendations for PA [20]. This lifestyle pattern may adversely affect the maintenance of body alignment and functional capacity.

Although PA has been proposed as a lifestyle-related factor associated with neck function and postural alignment, findings from previous studies directly examining the relationship between PA and FHP have been inconsistent. Some studies have identified PA as a factor significantly associated with FHP [21,22], whereas others have found no statistically significant association between these variables [23,24]. These discrepancies may be attributable not only to differences in participant characteristics, PA assessment methods, and postural measurement approaches, but also to the influence of neck function, which may be related to both PA and FHP. However, previous studies have mainly focused on the direct association between PA and FHP [21-24], with limited studies examining factors associated with CVA while simultaneously considering both PA level and neck function indicators. Therefore, to better interpret the inconsistent findings regarding the relationship between PA and FHP, analyses that consider both PA level and neck function indicators are needed.

Accordingly, this study aimed to compare differences in CVA and neck function indicators according to PA level among undergraduate and graduate students, and to examine the associations of PA level, cervical ROM, JPE, neck muscle strength, and neck muscle endurance with CVA. Furthermore, this study sought to identify key functional variables independently associated with CVA using stepwise regression analysis, incorporating both PA level and neck function indicators. Through this approach, this study aimed to provide additional insight into the inconsistent findings of previous studies regarding the relationship between PA and FHP from the perspective of neck function indicators, and to offer preliminary evidence for considering these indicators in the assessment of FHP in this population.

METHODS

1. Participants

This study included 102 undergraduate and graduate students. Participants were excluded if they had a history of cervical spine surgery or trauma, musculoskeletal injury, neurological disease, or recent cervical spine-related treatment. The required sample size was calculated using G*Power 3.1.9.4 (University of Kiel, Germany). Based on a statistical power of 0.85 and a significance level of 0.05, the minimum required sample size was estimated to be 96 participants. Considering a potential 5% dropout rate, a total of 102 participants were included in the final analysis. Participants were subsequently classified into PA-sufficient and PA-insufficient groups according to PA level, as assessed using the IPAQ-SF and based on whether they met the WHO adult PA guidelines. Prior to data collection, all participants received a detailed explanation of the study purpose and procedures, and written informed consent was obtained. This study was approved by the Institutional Review Board of Pukyong National University (approval No. PKNU202505006-UE001). The demographic characteristics of the participants are presented in Table 1.

Table 1.

Demographic characteristics of participants

2. Study procedures

Eligible participants were screened according to the inclusion criteria. Following a detailed explanation of the study procedures, written informed consent was obtained. Subsequently, CVA, cervical ROM, JPE, neck muscle strength, and neck muscle endurance were measured using standardized equipment. PA levels were assessed concurrently using a questionnaire. Participants were then classified into PA-sufficient and PA-insufficient groups based on their PA levels. Differences in CVA and neck function indicators were compared between the two groups. Subsequently, the associations of CVA with PA level and neck function indicators were examined, and stepwise regression analysis was performed to identify key functional indicators associated with CVA.

3. Measured variables

1) Forward head posture

Forward head posture was assessed using CVA. Lateral photographs were obtained while participants stood comfortably facing forward. The camera was positioned at a distance of 1.5 m from the participant, with its height adjusted to shoulder level. Participants were instructed to perform cervical flexion and extension movements and then return to a natural, comfortable posture. For CVA measurement, markers were placed on the tragus of the dominant side and the spinous process of the seventh cervical vertebra (C7). The CVA was defined as the angle between a horizontal line passing through the C7 spinous process and a line connecting the tragus to the C7 spinous process. A smaller CVA indicates a greater degree of FHP [25].

2) Physical activity level

Participants’ PA levels were assessed using the International Physical Activity Questionnaire-Short Form (IPAQ-SF). The IPAQ-SF is a 7-item self-report questionnaire that evaluates the frequency and duration of walking, moderate-intensity PA, and vigorous-intensity PA performed over the previous 7 days. In this study, walking, moderate-intensity PA, and vigorous-intensity PA were converted into metabolic equivalent minutes per week (MET-min/week) according to the IPAQ-SF scoring protocol. Specifically, 3.3 METs were assigned to walking, 4.0 METs to moderate-intensity PA, and 8.0 METs to vigorous-intensity PA. The MET-min/week for each activity was calculated by multiplying the assigned MET value by the duration of activity per day (min/day) and the number of days performed per week (days/week). Total PA was calculated as the sum of the MET-min/week values for walking, moderate-intensity PA, and vigorous-intensity PA. Participants were classified as PA-sufficient if they met the WHO adult PA guidelines, defined as engaging in at least 150 min/week of moderate-intensity PA, at least 75 min/week of vigorous-intensity PA, or an equivalent combination of both. Participants who did not meet these criteria were classified as PA-insufficient. The IPAQ-SF has been reported to demonstrate good reliability in university student populations (ICC=0.71-0.89) [26].

3) Cervical range of motion

Cervical range of motion (ROM) was quantitatively assessed using a cervical range of motion device (CROM Basic Spinal Assessment Device, Performance Attainment Associates, USA). Participants were seated upright in a chair with a backrest. The examiner secured the CROM device to the participant's head and measured ROM sequentially in cervical flexion, extension, and left and right rotation. Prior to data collection, participants performed one practice trial in each movement direction to become familiar with the procedure. Each movement direction was then measured three times, and the mean value was used for analysis. The CROM device has been reported to demonstrate high measurement reliability (ICC=0.87-0.94) [27].

4) Cervical joint position sense

Participants were seated upright in a chair with a backrest, with the hips and knees positioned at approximately 90° and the feet placed flat on the floor. The test was performed with participants’ eyes closed while wearing the CROM device. Following the assessment of cervical ROM, the examiner passively guided the participant's occiput to a target position, defined as 50% of the maximum ROM, and maintained this position for 5 s to enhance position awareness. Participants were then returned to the neutral position and instructed to actively reproduce the target position. Joint position error (JPE) was quantified as the angular difference between the target and reproduced positions [28]. Measurements were performed three times in each movement direction (flexion, extension, and left and right rotation), and the mean value was used for analysis. All measurements were conducted by the same examiner. Previous studies have reported that cervical joint position sense assessed using the CROM device demonstrates high reliability (ICC=0.89-0.98) [29].

5) Neck muscle strength

Neck muscle strength during isometric contraction of the cervical flexors and extensors was measured using a hand-held dynamometer (compuFET, Hoggan Health Industries Inc., West Jordan, Utah, USA) [30]. Dynamometer-based strength measurements have been reported to demonstrate high reliability (ICC=0.89-0.96) [31]. Neck flexor strength (NFS) was assessed with participants in the supine position, with the neck flexed to approximately 30° and the chin tucked. The examiner positioned the dynamometer at the center of the participant's forehead and applied resistance in the direction of cervical extension, while the participant maintained the flexed position and performed an isometric contraction. Neck extensor strength (NES) was assessed with participants in the prone position, with the shoulders positioned at the edge of the table and the head and neck maintained in a neutral position. The examiner positioned the dynamometer at the center of the occiput and applied resistance in the direction of cervical flexion, while the participant maintained the neutral position and performed an isometric contraction. A 1-min rest period was provided between trials and between muscle tests. Each test was performed three times, and the mean value was used for analysis. The measured force (N) for each muscle group was normalized to body weight (kg) [32].

6) Neck muscle endurance

Neck flexor endurance (NFE) was assessed with participants in the supine position on an examination table. The examiner placed one hand beneath the participant's occiput and instructed the participant to lift the head away from the examiner's hand while maintaining slight upper cervical flexion. During the test, verbal feedback was provided if the participant's head contacted the examiner's hand, and the test was terminated when the participant was unable to maintain the head in the elevated position. The holding time was recorded in seconds [33]. Neck extensor endurance (NEE) was assessed with participants positioned prone on the examination table, with both arms alongside the trunk and the head positioned beyond the edge of the table. A strap was secured at the level of the sixth thoracic vertebra (T6) to stabilize the upper thoracic spine. During the test, a Velcro band was fastened around the participant's head, and an inclinometer was attached over the occipital region. A 2-kg weight was suspended from the Velcro band, with its initial position set 2 cm above the floor. Participants were instructed to maintain the cervical spine in a horizontal neutral position throughout the test. The test was terminated if the weight contacted the floor or if the cervical angle deviated by more than 5° from the horizontal position. The holding time was recorded in seconds [34].

4. Statistical analysis

Data collected in this study were analyzed using IBM SPSS version 23.0 (IBM Corp.). The Shapiro-Wilk test was performed for all variables to assess the normality of the data distribution. Between-group differences in craniovertebral angle (CVA) and neck function indicators were analyzed using independent t-tests for normally distributed variables and the Mann-Whitney U test for non-normally distributed variables. Pearson or Spearman correlation analyses were then performed to examine the associations among CVA, PA level, and neck function indicators. Stepwise regression analysis was performed using cross-sectional data to identify key functional variables significantly associated with CVA. In this model, CVA was specified as the dependent variable, and PA level, cervical ROM, JPE, neck muscle strength, and neck muscle endurance were included as candidate predictors. Multicollinearity was assessed using the variance inflation factor (VIF<5), and model assumptions were evaluated using the Durbin-Watson statistic and residual analysis. The statistical significance level was set at α=0.05.

RESULTS

1. Descriptive statistics of PA level and neck function-related variables

Descriptive statistics for PA level and neck function-related variables are presented in Table 2. The mean PA level was 2,522.88±2,131.30 MET-min/week, indicating substantial interindividual variability. The mean CVA was 48.67±3.72°. Cervical ROM values were 59.17±9.11° for flexion (ROM-F), 72.46±11.42° for extension (ROM-E), 72.30±8.12° for left rotation (ROM-LRot), and 67.64±8.40° for right rotation (ROM-RRot). JPE values were 3.10±2.16° for flexion (JPE-F), 3.61±2.52° for extension (JPE-E), 3.96±2.40° for left rotation (JPE-LRot), and 3.98±2.83° for right rotation (JPE-RRot). For neck muscle function, NFS was 0.41± 0.10 N/kg, NES was 0.69±0.15 N/kg, NFE was 79.22±46.66 s, and NEE was 156.93±66.69 s.

Table 2.

Descriptive statistics of PA level and neck function variables

2. Comparison of CVA and neck function according to PA level

Comparisons of CVA and neck function indicators according to PA level are presented in Table 3. The PA-sufficient group demonstrated a significantly greater CVA than the PA-insufficient group (t=2.587, p =.010). The PA-sufficient group also showed significantly higher NFS (z=3.842, p <.001), NES (t=4.492, p <.001), and NFE (z=2.986, p =.003). In contrast, no significant between-group difference was observed in NEE (z=1.537, p =.124), and cervical ROM and JPE also did not differ significantly between the groups.

Table 3.

Comparison of CVA and neck function according to physical activity level

3. Correlations among CVA, PA level, and neck function

The correlations of CVA with PA level and neck function indicators are presented in Fig. 1. CVA was significantly and positively correlated with PA level (r=0.268, p <.01). CVA also showed significant positive correlations with cervical ROM in several movement directions, including ROM-F (r=0.316, p <.01), ROM-E (r=0.466, p <.01), and ROM-LRot (r=0.382, p <.01). In contrast, CVA was negatively correlated with JPE across all movement directions. Weak negative correlations were observed for JPE-F (r=-0.298, p <.01) and JPE-LRot (r=-0.291, p <.01), whereas moderate negative correlations were observed for JPE-E (r=-0.384, p <.01) and JPE-RRot (r=-0.420, p <.01).

Fig. 1.

Correlation analysis between forward head posture, physical activity, and neck function. Values represent correlation coefficients. *p<.05, **p<.01.

PA level was positively correlated with NFS (r=0.307, p <.01) and NES (r=0.259, p <.01). A significant positive correlation was also observed between PA level and NFE (r=0.207, p <.05). However, no significant correlations were observed between PA level and cervical ROM, JPE, or NEE (p>.05).

4. Stepwise regression analysis identifying factors associated with CVA

Stepwise multiple regression analysis was performed with CVA, representing FHP, as the dependent variable, and 13 indicators, including PA level, cervical ROM, and JPE, entered as candidate predictors. The overall regression model was statistically significant (F=19.146, p <.001). The model explained 49.9% of the variance in CVA (R²=0.499; adjusted R²=0.473). Multicollinearity diagnostics indicated that VIF values ranged from 1.081 to 1.303, all below the threshold of 5. The Durbin-Watson statistic was close to 2, suggesting no significant autocorrelation of residuals (Table 4). Significant predictors of CVA included ROM-E, JPE-LRot, JPE-RRot, ROM-F, and JPE-E (p <.05). Based on the magnitude of the standardized regression coefficients (β), the relative strength of association was as follows: ROM-E (β=0.400, p <.001), JPE-LRot (β= −0.296, p <.001), JPE-RRot (β=-0.206, p =.014), ROM-F (β=0.172, p =.024), and JPE-E (β=-0.165, p =.037).

Table 4.

Stepwise regression analysis of factors associated with craniovertebral angle

DISCUSSION

This study examined the associations among FHP, PA level, and neck function indicators in undergraduate and graduate students. The results indicated that students who met the WHO PA recommendations exhibited a greater CVA and significantly higher neck muscle strength (NFS and NES) and NFE compared with those who did not meet the recommendations. In addition, CVA was positively correlated with PA level (r=0.268, p <.01) and was also significantly associated with cervical ROM and JPE. In the stepwise regression analysis, cervical ROM- and JPE-related variables were identified as significant factors associated with CVA. The final model was statistically significant (F=19.146, p <.001) and explained 49.9% of the variance in CVA (R²=0.499, adjusted R²=0.473). These findings suggest that cervical ROM and JPE, together with PA level, may be relevant factors to consider when evaluating FHP in this population.

Between-group comparisons according to PA level indicated that the PA-sufficient group exhibited significantly higher CVA, NFS, NES, and NFE than the PA-insufficient group. In addition, PA level showed significant positive correlations with NFS (r=0.307, p <.01), NES (r=0.259, p <.01), and NFE (r=0.207, p <.05). Previous studies have suggested that insufficient PA may be associated with upper crossed syndrome or FHP-related characteristics [21,22], and regular exercise has been reported to be associated with improvements in neck muscle strength and reductions in neck and shoulder pain [35,36]. PA may influence blood supply, neuromuscular activation, and muscle fiber metabolic efficiency through repeated muscle contractions and loading stimuli [37,38]. These physiological adaptations may, in turn, contribute to the maintenance of neck flexor and extensor strength and flexor endurance. Taken together, these findings suggest that students who meet the recommended level of PA may exhibit relatively favorable cervical alignment and neck muscle function.

The present study also identified significant associations between CVA and cervical ROM. In the correlation analysis, CVA was positively correlated with ROM-F (r=0.316, p <.01), ROM-E (r=0.466, p <.01), and ROM-LRot (r=0.382, p <.01), suggesting that lower CVA values tended to be associated with more restricted cervical ROM. These findings are consistent with previous studies reporting associations between FHP and reduced cervical ROM. Basharat et al. [7] reported that FHP was associated with reduced cervical ROM in 400 female university students, and Tatsios et al. [39] similarly found a significant association between FHP measured using lateral photography and cervical ROM. Persistent FHP may be accompanied by alterations in the physiological curvature of the cervical spine and increased mechanical loading on cervical joints. In addition, stiffness and reduced elasticity of ligaments and periarticular soft tissues exposed to prolonged tension may be related to decreased cervical flexibility [40]. In the regression analysis, ROM-F and ROM-E were also identified as variables significantly associated with CVA, with ROM-E showing a relatively stronger association based on the standardized regression coefficient. Taken together, these findings suggest that ROM-F and ROM-E may reflect aspects of neck function associated with cervical alignment.

In addition, this study identified significant associations between CVA and JPE. In the correlation analysis, CVA was negatively correlated with JPE-F (r=-0.298, p <.01), JPE-E (r=-0.384, p <.01), JPE-LRot (r= −0.291, p <.01), and JPE-RRot (r=-0.420, p <.01), suggesting that lower CVA values were associated with greater cervical JPE. These findings are consistent with previous studies reporting associations between FHP and JPE. Abdel-Aziem et al. [9] reported that individuals with FHP exhibited greater JPE during cervical flexion, extension, and lateral flexion compared with those without FHP, and similar findings were reported by Aafreen et al. [41]. Persistent postural alignment changes, such as FHP, may be accompanied by imbalances in muscle tension and reduced soft tissue elasticity [12]. These alterations may be related to changes in the sensitivity of sensory receptors, including muscle spindles, and reduced accuracy of neuromuscular control [42]. However, as this study did not directly assess muscle spindle function or sensory receptor changes, the JPE findings should be interpreted as reflecting sensorimotor control characteristics rather than as direct evidence of these physiological mechanisms. Therefore, these findings suggest that JPE may reflect a sensorimotor control characteristic associated with cervical alignment.

This study has several limitations. First, PA level was assessed using the IPAQ-SF, a self-report questionnaire. Although the IPAQ-SF allows for convenient assessment of PA, it relies on participants’ recall of activities performed during the previous 7 days, which may introduce recall bias. In addition, social desirability bias may have contributed to overestimation or underestimation of actual PA levels. Second, stepwise regression analysis was used to identify variables associated with CVA. However, potential confounders such as sex, age, BMI, academic level, and sedentary time were not fully accounted for in the model. Moreover, the results of stepwise regression may be influenced by sample characteristics and the set of variables entered, and the variables retained in the final model may vary under different analytical conditions. Therefore, the ROM- and JPE-related variables identified in this study should be interpreted as exploratory factors associated with CVA rather than causal predictors. Third, this was a cross-sectional study conducted among undergraduate and graduate students from a single university, which may limit the representativeness of the sample and the generalizability of the findings. In addition, causal relationships among variables cannot be established. Future studies should further clarify the relationships among FHP, PA, and neck function using objective PA measurements (e.g., wearable devices), multicenter study designs, and longitudinal approaches.

CONCLUSION

This study examined the associations among PA level, FHP, and neck function indicators in undergraduate and graduate students. Students who met the WHO PA recommendations exhibited significantly greater CVA, NFS, NES, and NFE than those who did not meet the recommendations. In addition, PA level was positively correlated with NFS, NES, and NFE. CVA was also significantly associated with cervical ROM and JPE, particularly ROM-F, ROM-E, JPE-E, JPE-LRot, and JPE-RRot. Overall, these findings suggest that cervical ROM and JPE, along with PA level, may be relevant factors to consider when evaluating FHP in this population.

Notes

CONFLICT OF INTEREST

This work was supported by the Global Joint Research Program funded by the Pukyong National University (202506960001).

AUTHOR CONTRIBUTIONS

Conceptualization: Q Dong, ND Lim, IY Yu, H Choi, E Kim, TG Kim; Data curation: Q Dong; Formal analysis: Q Dong, H Ren; Funding acquisition: TG Kim; Methodology: ND Lim, IY Yu, H Ren, E Kim, TG Kim; Project administration: Q Dong, ND Lim, IY Yu, TG Kim; Visualization: ND Lim, IY Yu; Writing-original draft: Q Dong; Writing-review & editing: ND Lim, IY Yu, H Ren, GB Kim, E Kim, H Choi, TG Kim.

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Variable (n=102)	Mean±SD	Minimum-Maximum
Age (year)	26.40±4.89	18-37
Gender n (%)	Male 51 (50%)	Female 51 (50%)
Educational levels n (%)	Undergraduate 24 (23.50%)
	Master's Degree 34 (33.30%)
	Doctoral Degree 44 (43.10%)
Height (cm)	170.95±8.88	155-200
Weight (kg)	66.89±13.28	45-110
BMI (kg/m²)	22.65±2.75	17.53-29.20

Variable (n=102)	Mean±SD	Minimum-Maximum
PA	2,522.88±2,131.30	297.00-9,972.00
CVA (°)	48.67±3.72	38.60-57.00
ROM-F (°)	59.17±9.11	32.67-76.67
ROM-E (°)	72.46±11.42	42.67-99.33
ROM-LRot (°)	72.30±8.12	49.67-96.00
ROM-RRot (°)	67.64±8.40	48.00-88.67
JPE-F (°)	3.10±2.16	0-10.00
JPE-E (°)	3.61±2.52	0-10.67
JPE-LRot (°)	3.96±2.40	0.33-11.67
JPE-RRot (°)	3.98±2.83	0.67-13.67
NFS (N/kg)	0.41±0.10	0.22-0.72
NES (N/kg)	0.69±0.15	0.40-1.08
NFE (s)	79.22±46.66	16.00-244.00
NEE (s)	156.93±66.69	40.00-365.00

Variable	Analysis Type	PA level		t/z	p
Variable	Analysis Type	Sufficient	Insufficient	t/z	p
CVA	Nonparametric tests	49.68 (51.88-47.45)	47.43 (51.01-44.74)	2.587	.010*
ROM-F	t-test	60.35±8.87	57.95±9.29	1.338	.184
ROM-E	t-test	73.75±10.43	71.13±12.33	1.162	.248
ROM-LRot	t-test	72.76±7.13	71.83±9.09	0.576	.566
ROM-RRot	t-test	69.15±9.05	66.08±7.43	1.867	.065
JPE-F	Nonparametric tests	2.67 (4.00-1.67)	2.33 (3.50-1.58)	1.119	.263
JPE-E	Nonparametric tests	2.50 (4.50-1.33)	3.83 (6.00-1.67)	1.963	.050
JPE-LRot	Nonparametric tests	3.33 (5.33-2.00)	4.00 (6.00-2.00)	1.322	.186
JPE-RRot	Nonparametric tests	3.33 (5.33-2.00)	2.66 (5.42-2.00)	0.376	.707
NFS	Nonparametric tests	0.45 (0.51-0.37)	0.35 (0.43-0.30)	3.842	<.001***
NES	t-test	0.75±0.15	0.63±0.13	4.492	<.001***
NFE	Nonparametric tests	79.00 (123.00-59.50)	58.50 (85.25-38.75)	2.986	.003**
NEE	Nonparametric tests	154.00 (205.00-117.75)	126.50 (196.00-95.00)	1.537	.124

Variable	Regression coefficient (B)	Standard error (SE)	Standardized coefficient (β)	t	p	VIF
Constant	38.854	2.773	-	14.011	<.001***	-
ROM-F	0.070	0.031	0.172	2.285	.024*	1.081
ROM-E	0.130	0.025	0.400	5.149	<.001***	1.156
JPE-E	-0.243	0.115	-0.165	-2.110	.037*	1.167
JPE-LRot	-0.459	0.118	-0.296	-3.903	<.001***	1.106
JPE-RRot	-0.270	0.108	-0.206	-2.493	.014*	1.303
R²	0.499
Adjusted R²	0.473
D-W	1.985
F	19.146
P	<0.001