Study of the Validity and Reliability of Two Digital Dynamometers in Older People (SOVARDDIOP)

It is a cross-sectional, randomized, and single-center study with a duration of 6 months. The study will follow the STROBE guidelines for cross-sectional studies and CONSORT 2024. The main objective is to evaluate the validity and reliability of two devices in measuring grip strength and muscle fatigability in community-dwelling older adults.The study will include community-dwelling older adults of both sexes over 60 years of age.

Study Overview

• Status: Completed
• Conditions: Frailty; Sarcopenia; Old Age; Debility
• Intervention / Treatment: Diagnostic test: Validation and reliability

Detailed Description

Design: It is a cross-sectional, randomized, and single-center study with a duration of 6 months. The study will follow the STROBE guidelines for cross-sectional studies and CONSORT 2024. The main objective is to evaluate the validity and reliability of the Device 1 and Device 2 devices in measuring grip strength and muscle fatigability in community-dwelling older adults.

It will be carried out in two stages: In a first moment the criterion and interobserver validity will be assessed and in a second moment the intraobserver validity. Participants will be randomly assigned to one of the 6 arms to follow different orders of the devices (Device 1, Device 2 or Jamar).

Population: community-dwelling older adults of both sexes over 60 years of age.

Procedures: The investigators will schedule each participant for the initial assessment day. Using a table of random numbers, they will be assigned one of the arms. All participants have previously read, signed and given their written informed consent. An interview will be conducted in which age, sex and medication will be collected; an anthropometric and functional assessment will be performed. The functional tests include the 30-second squat test and grip strength tests using the Jamar, Device 1 and Device 2. Three repetitions will be performed with each device, allowing 30 seconds between repetitions and 3 to 5 minutes between devices. After 20 minutes the test will be repeated again on the devices for interobserver validation. 5 to 10 days later, tester 1 will repeat the grip test with the same effort to assess intraobserver reliability.

Sample size: Similar studies validating grip strength devices compared to the Jamar showed an excellent correlation (ICC > 0.90). With an estimated ICC of 0.90 ± 0.05 and an alpha risk of 5%, 348 participants are required for the training study.

Variables: Sociodemographic (age, sex, hand dominance, number of medication types), anthropometric (height, weight, BMI and SMI), strength and fatigability (total number of repetitions in 30sCS, maximal grip strength (HGS), fatigue resistance (FR) and grip work (GW)) and device preference.

Statistical analysis: Maximal strength and fatigability will be analyzed by means of means, standard deviations and statistical tests. Concordance between devices will be assessed using the Kappa coefficient and the Bland-Altman concordance index. ROC curves will be used to determine sensitivity and specificity, and data will be analyzed by gender. Results will be considered statistically significant if p < 0.05, and IBM SPSS Statistics v28.0 will be used for analysis.

• Study Type: Observational
• Enrollment (Actual): 413

Contacts and Locations

Study Locations

• Spain
  • Salamanca
    • Salamanca, Salamanca, Spain, 37007
      • University of Salamanca

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Community-dwelling older adults of both sexes over 60 years of age.

Description

Inclusion Criteria:

• Community-dwelling older adults of both sexes over 60 years of age.

Exclusion Criteria:

• Those who do not understand the orders given to them by the researcher or present an obvious advanced state of dementia.
• Those people who have amputation in one of the two upper limbs or who cannot perform manual grasping for any reason.
• Those who have had an episode of pain in one of the hands during the week prior to the measurement.
• Those who, due to any illness, prevent or contraindicate maximum resistance exercises.
• Any other cause that the research team assesses that may affect the results.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Device 1, Device 2 and Jamar®; As this is a validation study, both criterion, inter-observer and intra-observer validation will be performed. Initially, three repetitions will be performed with each device, leaving between 3 and 5 minutes of rest between devices. 20-30 minutes later, the same process will be repeated but with another researcher giving the orders (interobserver reliability). A few days later the same process is repeated with the first investigator (intra-observer reliability). No person will receive any treatment.

Diagnostic test: Validation and reliability; As this is a cross-sectional validation study, there is no intervention.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
2. Hand grip test	Measurement of hand grip strength using a hand-held dynamometer. Values shall be recorded with all three devices.	2 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Body Mass Index (BMI)	Is a mathematical ratio that associates the mass and the size of an individual BMI = weight / height ^2	2 weeks
4. Appendicular Skeletal Muscle mass Index (SMI)	Is a mathematical ratio that associates the muscle mass and the size of an individual SMI = appendicular muscle mass / height ^2	2 weeks
30 seconds chair stand test (30sCS)	Test that measures the number of times you perform the maximum number of squats on a chair in 30 seconds. The more squats the better functionally.	2 weeks
Fatigue resistance (FR)	Time taken to lose 50% of the maximum recorded grip strength.	2 weeks
Grip work (GW)	Value resulting from multiplying the maximum grip force by the fatigue strength by 0,75. It is measured in watts.	2 weeks

Collaborators and Investigators

• Sponsor: University of Salamanca
• Investigators: Principal Investigator: Luis Polo-Ferrero, PhD, University of Salamanca

Study record dates

Study Major Dates

• Study Start (Actual): December 16, 2024
• Primary Completion (Actual): March 31, 2025
• Study Completion (Actual): April 15, 2025

Study Registration Dates

• First Submitted: September 19, 2024
• First Submitted That Met QC Criteria: September 29, 2024
• First Posted (Actual): October 2, 2024

Study Record Updates

• Last Update Posted (Actual): December 18, 2025
• Last Update Submitted That Met QC Criteria: December 10, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: aged; Muscle Strength Dynamometer; Muscle Fatigue; Hand Strength; Jamar
• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Neuromuscular Manifestations; Pathologic Processes; Pathological Conditions, Anatomical; Muscular Atrophy; Atrophy; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Frailty; Sarcopenia
• Other Study ID Numbers: USalamancaValidityDinamometers

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No