Content area
Objectives
Despite the abundant evidence showing the benefits of muscle-strengthening exercise (MSE), no epidemiological tool is available for assessing MSE among Indonesian university students. This study is the first to adapt the Muscle-Strengthening Exercise Questionnaire (MSEQ) from its original English version into another language, specifically Indonesian, incorporating cultural adaptations and to pilot test it to assess its validity and reliability among university students in Indonesia.
Design
Translation and cultural adaptation, content validity studies, concurrent validity studies and reliability studies were conducted following COnsensus-based Standards for the Selection of Health Status Measurement INstruments guidelines. Content validation, conducted with three experts and nine university students, informed the development of the MSEQ Indonesian version. The concurrent validity study compared the results of measuring MSE frequency, intensity, duration and volume with those of the 7-day diary and relative handgrip strength with 22 respondents for concurrent validity against subjective measurement and 70 respondents for concurrent validity against objective measurement. For the reliability study, 39 respondents were asked to fill the MSEQ Indonesian version twice with a time interval of 7 days.
Settings and participants
The study involved 143 participants, including experts and university students from three universities across two different islands in Indonesia.
Results
Single administration MSEQ, consecutive administration MSEQ and 7-day diary recording resulted in 0%, 33.8% and 68.5% dropout rate, respectively. Moderate-to-strong correlations were observed between the results for the weekly frequency, duration, intensity and volume of MSE and those of the 7-day diary and hand grip strength. Test–retest reliabilities were good to excellent for machine weight, holistic and overall MSE but poor for bodyweight MSE. In assessing the target muscle group, the MSEQ Indonesian version showed good test–retest reliability for machine-weight MSE but poor-to-very good test–retest reliability for bodyweight, free weight and holistic MSE.
Conclusions
Our study demonstrated the acceptable validity and reliability of the Indonesian version of the MSEQ for assessing MSE among university students in Indonesia, not only by comparing each dimension of MSE with subjective measures but also by comparing MSE volume with objective measures. To enhance the generalisability of these findings, future studies should assess the MSEQ Indonesian version in diverse adult populations by considering dropout rates found by our study, ensuring its broader applicability and sample size adequacy.
Full text
Correspondence to Rahmaningsih Mara Sabirin; [email protected]
STRENGTHS AND LIMITATIONS OF THIS STUDY
This study used a systematic and rigorous cross-cultural adaptation process to translate the Muscle-Strengthening Exercise Questionnaire (MSEQ) for use in Indonesia.
The adapted version retained all original domains and included an additional construct to assess total muscle-strengthening exercise volume linked to a physiological outcome.
Following COnsensus-based Standards for the Selection of Health Status Measurement INstruments guidelines, we assessed both subjective and objective measures to ensure methodological robustness in examining preliminary validity and collected feasibility data to inform future validation studies.
The Indonesian version of the MSEQ, consistent with the original, does not capture key aspects such as repetitions, sets, rest periods and load-based intensity.
The study focused on university students, limiting its generalisability to middle-to-late adults.
Introduction
Recent guidelines strongly recommend adults to engage in muscle-strengthening physical activities (PAs) at least twice a week in addition to moderate to vigorous aerobic PA to acquire additional health benefits.1 Muscle-strengthening exercise (MSE) is a form of muscle-strengthening PA that uses weight training equipment, elastic bands, free weights or body weight and is performed during leisure time.2 In contrast to muscle-strengthening activities performed in occupational or domestic contexts, which may be associated with adverse musculoskeletal outcomes, MSE is supported by robust and consistent evidence demonstrating association with reduced all-cause mortality and non-communicable diseases (NCDs).3 4
In addition to its well-established physical health benefits, MSE has been associated with academic benefits both through biological and psychosocial mechanisms.5 MSEs have been shown to improve cognitive function6 and cardiometabolic health,7 8 both of which could directly and indirectly influence academic performance.9 10 Improvement of brain volume,11 neuroplasticity,12 neurogenesis,13 improvement in self-confidence,14 anxiolytic effects15 and well-being16 were among the proposed mediators of MSE benefits on academic performance through psychosocial mechanisms.
Despite the potential benefits, national surveillance data indicate a declining trend in PA levels in Indonesia, with the proportion of individuals meeting recommended guidelines falling from 77.9% in 2013 to 62.6% in 2023.17–20 Furthermore, university students appear to be less physically active than the general Indonesian population, with only 45.0% university students reporting sufficient PA.21 Insufficient PA among university students may contribute to an increased risk of NCDs and suboptimal academic performance, both of which have the potential to reduce future workforce productivity and undermine the prospects of Indonesia’s demographic dividend.22
To mitigate these risks, systematic monitoring of muscle-strengthening PA among university students is essential. However, no surveillance system comprehensively covering the important dimensions of muscle-strengthening PA is available in many countries, including Indonesia.18–20 23 The Muscle-Strengthening Exercise Questionnaire (MSEQ) is a valid and reliable instrument designed to assess MSE in an online, self-report format developed for the adult population.24 The questionnaire was developed and validated among English-speaking populations in Australia, which has also been used in several studies in the USA.24–27 The long form of the MSEQ consists of 20 items and assesses specific dimensions of MSE, including (1) frequency, (2) intensity, (3) duration, (4) type of exercise, machine weight, bodyweight, free weights and holistic training and (5) targeted muscle groups, such as the legs, hips, back, abdomen, chest, shoulders and arms.24 A shorter version with six items is also available, which assesses overall frequency, duration, intensity, types of MSE and targeted muscle groups.24
To date, the MSEQ has not been translated into Bahasa Indonesia or adapted for use in the Indonesian context. The only available questionnaires for assessing PA and which have been tested for validity and reliability in Indonesia are Indonesian adaptation of the International Physical Activity Questionnaire (IPAQ),28 29 Indonesian version of the Godin-Shepard’s Leisure time Physical Activity Questionnaire (PAQ),30 Indonesian version of the PAQ for adolescents (PAQ-A) and older children (PAQ-C)31 and the PAQ-A.32 None of them assessed MSE components. In addition, there is also no study reporting comprehensive processes of translation and adaptation of PA questionnaire to Indonesian context, nor reporting their measurement properties according to the standard reporting of questionnaire measurement guidelines.33 Therefore, our study is the first study aimed at adapting and translating the MSEQ to Bahasa Indonesia. Additionally, we also aimed to conduct a pilot test observing any problems and feasibility aspects in examining the validity and reliability of the MSEQ Bahasa Indonesia version among university students.
Methods
We followed the COnsensus-based Standards for the Selection of Health Status Measurement INstruments (COSMIN) guidelines33 to report the translation and adaptation processes, as well as the property measurements (online supplemental material 1).
The MSEQ long form was translated to Bahasa Indonesia and culturally adapted to the Indonesian context by employing Beaton’s and Sousa’s guidelines and a previous questionnaire translation study (figure 1).34–36 The initial Indonesian version of the questionnaire was revised according to the results of content validation. Then, we pilot-tested it to examine the concurrent validity and reliability of the final version among university students and to report dropout rates and other problems that arose. Owing to the limited evidence on the gold standard for assessing the frequency, intensity, type, duration and target muscle group of MSE in free-living contexts, concurrent validity was assessed rather than criterion validity to determine the extent of its agreement with the other non-criterion measures of MSE.37 38 Confirmatory factor analysis (CFA) was not conducted because the MSEQ was intentionally designed with single items to measure each distinct dimension of MSE (frequency, intensity, duration, type of exercise and targeted muscle groups). As CFA is used to evaluate structural validity by examining how multiple items load onto a common latent factor, it is not appropriate for instruments like the MSEQ, which do not contain item groupings intended to reflect a single underlying construct.39
Figure 1. Questionnaire development process. MSEQ, Muscle-Strengthening Exercise Questionnaire; PI-FTL, prefinal version of the translated version.
Translation
Forward translations were conducted by two independent translators to translate the English/original version to Bahasa Indonesia, producing translation I (TL I) and translation II (TL II). The first translator is an Indonesian who has excellent English proficiency and is naïve in the PA field, and the second translator is an Indonesian who has excellent English proficiency and a master’s degree in the PA field. A committee consisting of four researchers covering three academic fields (PA for health, medicine and physiotherapy) compared TL I and TL II with the English/original version in the aspects of completeness, appropriateness and comprehension and synthesised a preliminary initial translated version (PI-TL). The committee then assessed the content validity of PI-TL by interviewing experts and discussing with non-expert informants. On the basis of the results, the committee discussed and revised PI-TL into a prefinal version of the translated version (P-FTL). Backward translations were independently conducted by the third and fourth translators, producing back translation version I (BTL I) and back translation version II (BTL II) (online supplemental material 2), respectively. The third translator is a UK English native who is naïve to the PA field and has lived in Indonesia for more than 20 years, and the fourth translator is an Indonesian who has lived in the UK for more than 10 years. Finally, a committee compared BTL I and BTL II to the original version, synthesised a FTL, and created guidelines and template to score and analyse the MSEQ Indonesian version (online supplemental materials 3,4). The FTL was then tested for concurrent validity and reliability.
Validity study
Content validity
Content validity assessments using a mixed-method approach were conducted during the translation and cross-cultural adaptation to assess the completeness, appropriateness and comprehension of PI-TL. Purposive sampling was conducted in July 2022 to recruit experts (a public health researcher, an exercise science researcher and a practitioner) and non-experts representing university students. Guided by interview and discussion guides (online supplemental material 5), interviews with experts and Focus Group Discussions (FGDs) with nine university students were conducted. All interviews and group discussions were audio recorded and then transcribed verbatim. Using the framework method of thematic analysis, two researchers (RSA and MNT) independently analysed the verbatim transcripts from interviews and group discussions.40 In addition, a survey using the COSMIN questionnaire for assessing content validity41 (online supplemental material 6) was administered to the experts and non-expert informants before the interview or group discussion to examine the content validity of PI-TL. The total score was 50 points, representing 25 points of completeness, 5 points of relevance and 20 points of comprehension. The expert and non-expert informants were then asked to assess the completeness, appropriateness and comprehension of P-FTL using a similar questionnaire for content validity assessment.
Concurrent validity
Concurrent validity was assessed by comparing the final version of the Indonesian MSEQ (online supplemental material 7) to a 7-day diary as a subjective criterion measure and handgrip strength (HGS) as an objective criterion measure. The 7-day diary was chosen because of its short recall period, resulting in high accuracy in capturing behaviours.42 Meanwhile, HGS was chosen because it represents a physiological measure of the MSE’s habit effect.43 HGS is a valuable indicator of overall muscle strength and is widely used as a screening tool due to its simplicity, low-cost reliability and strong association with health outcomes.44–47 In contrast to push-ups and sit-ups, which are based on repetition counts and primarily assess specific muscle groups, HGS provides a standardised, continuous measurement (in kilograms) that reflects upper body and overall strength.48 For the pilot study, 66 respondents were set as the minimum sample population to adequately assess and identify problems to anticipate 10.6% inattentive responses.49 50 Students were conveniently recruited from a public university in Java Island, Indonesia over a 2-week period from the last week of August to the first week of September 2022. HGS was assessed on their dominant hand in the morning following the Southampton protocol using a hand dynamometer (Camry EH101, Zhongshan Camry Electronic, China).51 The age-specific and sex-specific z-score of BMI-adjusted absolute maximal HGS was used to consider the age-dependent, sex-dependent and BMI-dependent HGS normative data.52–55 On the same day before the HGS assessment, the respondents were asked to fill out the self-administered MSEQ Indonesian online form, followed by the 7-day diary for 7 consecutive days. The researchers provided a daily reminder for the respondents. The respondents who failed to fill the diary in 24 hours were categorised as dropouts.
Reliability study
A minimum sample of 73 respondents was set to adequately examine the test–retest reliability of the MSEQ Indonesian version by anticipating 20% dropout and 10.6% inattentive response.49 We recruited a different sample for the reliability study than for the validity study to minimise participant burden from time-intensive procedures, such as HGS testing and a 7-day diary, and to improve the representativeness of the reliability sample by enabling broader recruitment beyond the in-person setting required for HGS assessment.56 To enhance geographical diversity, since most previous questionnaire evaluations in Indonesia have been conducted on Java Island,28–32 34 57 a convenient sampling was conducted in one public and one private university on Java Island and a public university on Sumatra Island through social media from the last week of October to the first week of November 2022. The respondents were asked to fill out the self-administered MSEQ Indonesian version online form twice at a 7-day interval.
Statistical analysis
Data were analysed using the Statistical Package for the Social Sciences V.22 (SPSS, IBM). Correlation between MSEQ and 7-day diary was examined using Spearman rank correlation due to the skewed data, and categorised as strong (at least 0.8), moderately strong (0.6–0.8), fair (0.3–0.5) or poor (<0.3).58 Bland-Altman plots were also created to report the mean of the difference and precision for the agreement between the questionnaire and the diary.59 The mean of the difference below half of twice a week of MSPAs was considered acceptable as suggested by the guidelines.1 Partial correlation tests controlling for BMI were conducted between the HGS z-score and the weekly frequency, weekly duration, average weekly intensity and total weekly volume of MSE to examine the concurrent validity of the MSEQ Indonesian version to the physiological outcomes of MSE. Calculations were conducted for the intraclass correlation coefficient (ICC) of the weekly frequency, duration, volume and average intensity of MSE and the Cohen’s kappa and agreement of the target muscle group captured using the MSEQ Indonesian version. ICC values less than 0.5 were categorised as poor, 0.5–0.75 as moderate, 0.75–0.9 as good and greater than 0.90 as excellent reliability.60 Cohen’s kappa less than 0.2 was categorised as poor, 0.21 to 0.4 as fair, 0.41–0.6 as moderate, 0.61–0.8 as good and 0.81–1 as very good.61 Given the small sample size in this pilot study, statistical analyses were conducted to provide preliminary evidence on the concurrent validity and reliability of the MSEQ Indonesian version, as well as estimates of variability, rather than to support formal testing. These analyses, combined with feasibility data, are intended to inform sample size calculations, recruitment strategies and other design aspects for a more robust future study to confirm the psychometric properties of the questionnaire.62
Patient and public involvement
We involved experts from different fields and university students through interviews and group discussions to the content validity of the questionnaire.
Results
Our study flow and characteristics of respondents are summarised in figure 1 and table 1.
Table 1
Respondents’ characteristics
| Content validity | Concurrent validity | Reliability (n=39) | ||
| FGD sources (n=9) | Subjective (n=22) | Objective (n=70) | ||
| Age | ||||
| Median (min to max) (years) | 22 (20 to 34) | 21 (20 to 37) | 20 (19 to 37) | 20 (18 to 32) |
| Sex | ||||
| Male (n (%)) | 2 (22.2%) | 2 (9.1%) | 9 (12.8%) | 13 (26.7%) |
| Female (n (%)) | 7 (77.8%) | 20 (90.9%) | 61 (87.2%) | 88 (73.3%) |
| Level of study | ||||
| Undergraduate (n (%)) | 5 (55.6%) | 21 (95.4%) | 69 (98.5%) | 26 (71.1%) |
| Postgraduate (n (%)) | 4 (44.4%) | 1 (4.6%) | 1 (1.5%) | 13 (28.9%) |
| Field of study | ||||
| Social sciences (n (%)) | 3 (33.3%) | – | 6 (8.6%) | 23 (51.1%) |
| Health sciences (n (%)) | 5 (55.6%) | 22 (100%) | 61 (87.1%) | 13 (28.9%) |
| Natural sciences (n (%)) | 1 (11.1%) | – | 3 (4.3%) | 9 (20%) |
| Type of residence | ||||
| Private rent (n (%)) | 6 (66.7%) | 14 (63.7%) | 40 (57.1%) | 31 (68.9%) |
| University dormitory (n (%)) | 1 (11.1%) | 1 (4.6%) | 7 (10%) | 2 (4.4%) |
| With parents (n (%)) | 2 (22.2%) | 7 (31.7%) | 23 (32.9%) | 12 (26.7%) |
| Type of university | ||||
| Private | 0 (0%) | 0 (0%) | 0 (0%) | 12 (26.7%) |
| Public | 9 (100%) | 22 (100%) | 70 (100%) | 27 (73.3%) |
| Geographical location | ||||
| Java | 9 (100%) | 22 (100%) | 70 (100%) | 32 (82.1%) |
| Non-Java | 0 (0%) | 0 (0%) | 0 (0%) | 7 (17.9%) |
FGD, Focus Group Discussion; n, number.
Participants who consented to participate in the concurrent validity study were predominantly health science students. Those who dropped out of the 7-day diary study shared similar characteristics with those who completed it; most were female, undergraduate students and lived in private rented accommodation (table 2). In contrast, postgraduate students were more likely to drop out of the reliability study.
Table 2
Characteristics of dropped out respondents
| Content validity | Concurrent validity | Reliability (n=20) | ||
| FGD sources (n=0) | Subjective (n=48) | Objective (n=0) | ||
| Age | ||||
| Median (min to max) (years) | – | 20 (19 to 24) | – | 20 (18 to 25) |
| Sex | ||||
| Male (n (%)) | – | 8 (16.7%) | – | 7 (35%) |
| Female (n (%)) | – | 40 (83.3%) | – | 13 (65%) |
| Level of study | ||||
| Undergraduate (n (%)) | – | 47 (97.9%) | – | 1 (5%) |
| Postgraduate (n (%)) | – | 1 (2.1%) | – | 19 (95%) |
| Field of study | ||||
| Social sciences (n (%)) | – | 5 (10.4%) | – | 8 (40%) |
| Health sciences (n (%)) | – | 42 (87.5%) | – | 12 (60%) |
| Natural sciences (n (%)) | – | 1 (2.1%) | – | 0 (0%) |
| Type of residence | ||||
| Private rent (n (%)) | – | 26 (54.2%) | – | 12 (60%) |
| University dormitory (n (%)) | – | 6 (12.5%) | – | 2 (10%) |
| With parents (n (%)) | – | 16 (33.3%) | – | 6 (30%) |
| Type of university | ||||
| Private | – | 0 (0%) | – | 3 (15%) |
| Public | – | 48 (100%) | – | 17 (85%) |
| Geographical location | ||||
| Java | – | 48 (100%) | – | 14 (70%) |
| Non-Java | – | 0 (0%) | – | 6 (30%) |
FGD, Focus Group Discussion; n, number.
Content validity
We made several adjustments to the questionnaire, including adding and adjusting illustrations; customising the options; adding day options to frequency questions; explaining intensity, exercise type and duration; adding pages; adjusting layout and emphasising some explanations by applying bold marks (online supplemental material 8). Before the adjustments, the questionnaire got a score of 40.89 points, consisting of 20.11 points for relevance, 4.11 points for comprehensiveness and 16.67 points for comprehension. Points for relevance (20.56 points), comprehensiveness (4.22 points) and comprehensibility (17.56 points) increased after the adjustment, resulting in a total of 42.34 points.
Subjective concurrent validity
Data from 22 out of the 71 recruited respondents were analysed to examine the concurrent validity of the MSEQ Indonesian version against the 7-day diary. However, 49 respondents dropped out from the 7-day diary recording, leaving only 22 respondents for analysis. Most of the respondents in the final analysis were female (90.9%), undergraduate students (95.4%) and lived in a private-rented house (63.7%) (table 1).
All the MSE dimensions had a strong correlation (r range from 0.73 to 0.82) (table 3). Bland-Altman plots showed that the Indonesian MSEQ can be considered acceptable to measure all the MSE dimensions, with a slight overestimation of duration and intensity and underestimation of volume at +0.09 min/week, +0.15 MET and −56.95 MET min/week, respectively (figure 2).
Table 3
Spearman test relative 7-day diary and HGS to MSE frequency, duration, average intensity and volume of MSEQ
| Measurement | Dimension of MSE | Spearman rho | p value |
| 7-day diary | Frequency | 0.82 (95% CI 0.60 to 0.92) | 0.000* |
| Duration | 0.81 (95% CI 0.58 to 0.92) | 0.000* | |
| Average intensity | 0.73 (95% CI 0.45 to 0.88) | 0.000* | |
| Volume | 0.81 (95% CI 0.59 to 0.92) | 0.000* | |
| Hand-grip strength | Frequency | 0.35 (95% CI 0.25 to 0.77) | 0.003* |
| Duration | 0.30 (95% CI 0.12 to 0.54) | 0.011* | |
| Average intensity | 0.32 (95% CI 0.07 to 0.50) | 0.006* | |
| Volume | 0.35 (95% CI 0.10 to 0.52) | 0.003* |
*Statistically significant at 0.05 level of significance.
HGS, handgrip strength; MSE, muscle-strengthening exercise; MSEQ, Muscle-Strengthening Exercise Questionnaire.
Objective concurrent validity study
Data from 71 respondents were examined to examine the concurrent validities of MSE reported through the MSEQ Indonesian version against the relative maximal HGS as physiological outcomes (figure 1). No respondent dropped out. Most of the respondents in the final analysis were female (87.2%), undergraduate students (98.5%) and lived in a private-rented house (57.1%) (table 1). A moderate correlation (r range from 0.30 to 0.35) was observed between the relative maximum HGS and the frequency, duration, average intensity and volume of MSE in the MSEQ (table 3).
Reliability study
Twenty of fifty-nine respondents did not respond to the second administration of the MSEQ in the reliability study, resulting in a dropout rate of 33.8% (figure 1). The MSEQ Indonesian version showed moderate-to-excellent test–retest reliability (ICC range from 0.54 to 0.99) in assessing the frequency, duration, intensity and volume of machine weight, free weight, holistic and overall MSE. Its reliability was poor in examining body weight MSE (ICC range from 0.23 to 0.48) for all dimensions (table 4) and poor-to-very good (Cohen’s kappa range from −0.13 to 0.79) in assessing the target muscle groups of body weight, free weight and holistic MSE (table 5). Meanwhile, it had very good reliability in assessing the target muscle groups of machine-weight MSE (Cohen’s kappa range from 0.84 to 1) (table 5).
Table 4
ICC analysis results of reliability study
| Data types | ICC | 95% Confidence Interval (CI) | |
| Lower bound | Upper bound | ||
| Overall MSE | |||
| Frequency | 0.71 | 0.50 | 0.83 |
| Average intensity | 0.54 | 0.27 | 0.73 |
| Duration | 0.97 | 0.95 | 0.99 |
| Volume | 0.98 | 0.96 | 0.99 |
| Machine weight | |||
| Frequency | 0.95 | 0.91 | 0.98 |
| Average intensity | 0.89 | 0.79 | 0.94 |
| Duration | 0.98 | 0.95 | 0.99 |
| Volume | 0.98 | 0.97 | 0.99 |
| Bodyweight | |||
| Frequency | 0.39 | 0.09 | 0.63 |
| Average intensity | 0.48 | 0.21 | 0.69 |
| Duration | 0.36 | 0.07 | 0.60 |
| Volume | 0.23 | −0.07 | 0.50 |
| Free weight | |||
| Frequency | 0.82 | 0.68 | 0.90 |
| Average intensity | 0.70 | 0.49 | 0.83 |
| Duration | 0.99 | 0.98 | 1.00 |
| Volume | 0.99 | 0.97 | 0.99 |
| Holistic | |||
| Frequency | 0.92 | 0.85 | 0.96 |
| Average intensity | 0.93 | 0.87 | 0.96 |
| Duration | 0.90 | 0.83 | 0.95 |
| Volume | 0.97 | 0.94 | 0.98 |
ICC, intraclass correlation coefficient; MSE, muscle-strengthening exercise.
Table 5
Cohen’s kappa analysis result of reliability study
| Domains | Cohen’s kappa coefficient (SE of kappa) | 95% Convidence Interval (CI) | Percentage agreement (%) | |
| Lower limit | Upper limit | |||
| Machine weight | ||||
| Legs | 1 (0) | 1 | 1 | 100 |
| Hips | 1 (0) | 1 | 1 | 100 |
| Back | 1 (0) | 1 | 1 | 100 |
| Abdomen | 1 (0) | 1 | 1 | 100 |
| Chest | 0.84 (0.15) | 0.54 | 0.14 | 97.4 |
| Shoulders | 0.84 (0.15) | 0.54 | 0.14 | 97.4 |
| Arms | 0.84 (0.15) | 0.54 | 0.14 | 97.4 |
| Bodyweight | ||||
| Legs | 0.66 (0.13) | 0.41 | 0.90 | 84.6 |
| Hips | 0.36 (0.19) | −0.01 | 0.73 | 82.05 |
| Back | −0.13 (0.06) | −0.24 | −0.01 | 71.8 |
| Abdomen | 0.47 (0.15) | 0.18 | 0.76 | 76.9 |
| Chest | 0.36 (0.19) | −0.03 | −0.74 | 82.05 |
| Shoulders | −0.11 (0.05) | −0.21 | −0.02 | 76.9 |
| Arms | 0.27 (0.16) | −0.04 | 0.58 | 79.5 |
| Free weight | ||||
| Legs | 0.79 (0.21) | 0.38 | 1.19 | 97.4 |
| Hips | 0.47 (0.32) | −0.15 | 1.09 | 94.9 |
| Back | 0.66 (0.32) | 0.03 | 1.28 | 97.4 |
| Abdomen | −0.04 (0.03) | −0.08 | 0.01 | 92.3 |
| Chest | 0.47 (0.32) | −0.15 | 1.09 | 94.9 |
| Shoulders | −0.07 (0.03) | −0.13 | 0.00 | 87.2 |
| Arms | 0.64 (0.24) | 0.18 | 1.10 | 94.9 |
| Holistic | ||||
| Legs | – | – | – | 97.4 |
| Hips | 0.64 (0.24) | 0.18 | 1.10 | 94.9 |
| Back | −0.03 (0.02) | −0.06 | 0.01 | 94.9 |
| Abdomen | 0.64 (0.23) | 0.19 | 1.09 | 94.9 |
| Chest | 0.66 (0.32) | 0.03 | 1.28 | 97.4 |
| Shoulders | – | – | – | 97.4 |
| Arms | 0.48 (0.31) | −0.12 | 1.08 | 94.9 |
Discussion
Our study reported the translation and adaptation of the MSEQ into its Indonesian version. We have made several modifications based on themes developed by end-users’ and experts’ opinions. Owing to the translation and cultural adaptation, an improvement was observed from 40.89 to 42.34 of the 50 score of the COSMIN quantitative questionnaire for assessing content validity.39 41 In this pilot study, the MSEQ Indonesian version showed strong correlation and good precision with the 7-day diary but a weak correlation with HGS. It also had acceptable test–retest reliability in assessing the frequency, intensity, duration and volume of MSE. However, it only showed acceptable reliability in assessing the targeted muscle groups of machine-weight MSE. These findings should be interpreted with caution, as the limited sample size in this pilot study was intended to yield preliminary evidence and estimate variability to inform future studies, rather than to support definitive conclusions. A larger sample would enable more robust statistical analyses and improve the generalisability and power of the results. Importantly, this study also provided initial feasibility data, including recruitment and dropout rates, to inform the design of future larger-scale studies.
Compared with the original version, the MSEQ Indonesian version had higher test–retest reliability (ICC range from 0.51 to 0.96 and from 0.54 to 0.97, respectively) and concurrent validity (ρ range from 0.30 to 0.77 and from 0.73 to 0.82, respectively) in assessing the frequency, duration and intensity of overall MSE.24 This finding indicated that the addition of definition and explanation questions enhanced the comprehension of the MSEQ Indonesian version and consequently its reliability and validity.63 Although they failed to improve the validity of GPAQ in assessing the intensity of aerobic activity,64 the show cards illustrating MSE examples might have helped the subjects identify the type of MSE they engaged in because MSE might be harder to understand than aerobic activities.65 The provided list of days in the option to recall the frequency of MSE functioned as memory cues that helped the subjects recall their behaviour; this phenomenon can also explain the improvement in the validity and reliability of the MSEQ Indonesian version.66 Meanwhile, the addition of several components helped the subjects identify and recall their MSE behaviour but also resulted in a high burden for them, leading to loss of interest and an increase in non-response items.67–71 Our study found a 0% dropout rate for a single administration of MSEQ and a 33.8% dropout rate for two consecutive administrations of MSEQ at a 7-day interval. Future studies using the MSEQ Indonesian version are recommended to use reminders and prenotification to maintain the completion rate.68 70 In addition, the dropout rate of the 7-day diary as a concurrent validity comparator was 68.5%%. This high rate was primarily due to participant burden, as the diary required daily entries over a 1-week period, which some participants found difficult to maintain.72 As this was a pilot study intended to inform a future larger study, the observed dropout rate provides valuable insight into participant adherence and can help guide recruitment strategies in future studies using 7-day diaries as their measurement tools.
The MSEQ Indonesian version’s test–retest reliability score had an almost similar pattern to the original version in assessing target muscle groups. It also had an almost perfect agreement in assessing target muscle groups during MSE using weight machines (Cohen’s kappa range from 0.84 to 1). Several experts argued that MSE using weight machines is easier and does not require complex knowledge compared with the other MSE domains.73 Therefore, users may find it easier to recall their MSE using weight machines compared with the other MSE domains. The high dropout rate among postgraduate students in the test–retest reliability study should be noted in future research planning, particularly for longitudinal assessments using the MSEQ. Although the final sample’s composition remained broadly consistent with the national distribution of undergraduate and postgraduate students in Indonesia, the observed dropout pattern suggests that postgraduate students may face greater challenges in completing follow-up assessments, possibly due to time constraints or academic workload.74 Tailored retention strategies may be needed to support this subgroup in future studies.
In addition to the MSEQ, several questionnaires have recently been developed to assess MSE, including the 2015 Behavioural Risk Factor Surveillance System (BRFSS) for assessing the weekly frequency of MSE,75 the Cancer Prevention Study-3 (CPS-3) for assessing the weekly duration of MSE,76 and the Muscle-Strengthening Activity Scale (MSAS) for assessing the frequency and duration of muscle-strengthening activities.77 Owing to the nature of the comprehensive items in the MSEQ Indonesian version, our pilot validity study found the higher validity of the MSEQ Indonesian version for assessing the weekly frequency and duration of MSE compared with the BRFSS in assessing whether participants met the recommended muscle-strengthening activities engagement at least twice per week (Cohen’s kappa range 0.40–0.52)75 and the CPS-3 in assessing the weekly duration of MSE (Spearman correlation of 0.71).76 The MSAS uses seven items to assess the frequency and duration of muscle-strengthening PA, but no study has assessed its validity to date.78
The MSEQ Indonesian version showed better concurrent validity (r range from 0.30 to 0.36) against HGS than the available questionnaires, including the muscle-strengthening activity question of the European Health Interview Survey-PAQ and the total activity of the IPAQ-Long Form.79 Therefore, the MSEQ Indonesian version could be used in examining the dose–response relationship of frequency, intensity, duration and volume with muscle strength, which requires further epidemiological studies.80 81
By considering the feedback and suggestions from end-users and experts from multidisciplinary teams, we translated and culturally adapted the MSEQ into its Indonesian version. The Indonesian version showed good validity and reliability for assessing the frequency, duration, intensity, volume, target muscle group and different types of MSE. Although no gold standard is available for assessing all constructs of the MSE, we conducted construct validation studies using subjective and objective measures. In addition, we designed and reported our study under the COSMIN guidelines and provided detailed explanations of the terminologies used in our study to resolve several limitations of previous investigations, including poor methodologies and ambiguity of terminologies, as identified by a recent systematic review.82
Limitations
The MSEQ Indonesian version could not cover all the dimensions of MSE, particularly repetition, number of sets, rest between periods and load-based intensity as these dimensions were not included in the original MSEQ.24 83 However, we added a combination of the four main dimensions of MSE (frequency, intensity, duration and type of exercise) into the MSEQ Indonesian version to enable the analysis of weekly MSE volume which was not covered in the original MSEQ. Another limitation of our study was the representativeness of our respondents in the concurrent validity and reliability study which might not be fully generalised to middle-to-late adults. While our concurrent validity study recruited students from a single university due to the feasibility of conducting HGS measurements, we specifically selected this university for its representativeness of the Indonesian population, as nearly 20% of its students come from outside Java Island. However, we were unable to confirm the geographical representativeness of our sample, as data on participants’ high school location, an important proxy for prior regional exposure, were not collected. Additionally, we strengthened the generalisability of our reliability findings to the broader university student population by including respondents from three universities, representing two types of institutions and two distinct geographical locations, which are currently major factors influencing sociodemographic and health determinants in Indonesia.57 Our subjective validity findings were affected by a large proportion of missing data with a non-normal distribution, making imputation inappropriate. This limitation calls for further examination of the subjective validity of the Indonesian version of the MSEQ in future studies.84 85 Nevertheless, our study provided several important feasibility outcomes, including recruitment rates and dropout rates, which can be used in designing further large studies with representative respondents, either Indonesian university students or general Indonesian adults.86
Conclusions
The MSEQ Indonesian version showed acceptable preliminary validity and reliability for assessing the weekly frequency, weekly duration, average intensity, weekly volume and targeted muscle groups of MSE among university students. Our study expands the original MSEQ utility to assess each domain, also incorporating the evaluation of MSE volume, which correlates with both physiological and health outcomes. Future studies should build on our pilot results, including dropout rates, to validate the Indonesian MSEQ with a diverse adult population, particularly middle-to-late adults, using a sufficient sample size.
Contributors RSA and RAW conceptualised and designed the study. RSA, DAP and MNT collected the data. RAW and RMS monitored the data collection. RSA and MNT analysed the qualitative data. RSA, STBM and RAW analysed the quantitative data. RSA drafted and revised the manuscript; RMS, STBM, DAP, MNT and RAW wrote and revised the manuscript. RMS is the guarantor.
Funding This research was supported by the Junior Researcher Grant, Faculty of Medicine, Public Health and Nursing, Universitas Gadjah Mada (Ref No:324 /UN1/FKKMK/PPKE/PT/2022).
Disclaimer The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests None declared.
Patient and public involvement Patients and/or the public were involved in the design, or conduct, or reporting, or dissemination plans of this research. Refer to the Methods section for further details.
Provenance and peer review Not commissioned; externally peer reviewed.
Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.
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