Reliability and validity of the 6-min walk test in adults and seniors with intellectual disabilities

Myriam Guerra-Balic; Guillermo R Oviedo; Casimiro Javierre; Jesús Fortuño; Silvia Barnet-López; Oscar Niño; Juan Alamo; Bo Fernhall

doi:10.1016/j.ridd.2015.09.011

Reliability and validity of the 6-min walk test in adults and seniors with intellectual disabilities

Res Dev Disabil. 2015 Dec:47:144-53. doi: 10.1016/j.ridd.2015.09.011. Epub 2015 Sep 29.

Authors

Myriam Guerra-Balic¹, Guillermo R Oviedo², Casimiro Javierre³, Jesús Fortuño⁴, Silvia Barnet-López⁵, Oscar Niño⁶, Juan Alamo⁷, Bo Fernhall⁸

Affiliations

¹ FPCEE-Blanquerna, University Ramon Llull, c/ Cister 34, Barcelona 08022, Spain. Electronic address: miriamelisagb@blanquerna.url.edu.
² FPCEE-Blanquerna, University Ramon Llull, c/ Cister 34, Barcelona 08022, Spain; School of Biokinetics, Recreation and Sport Science, North-West University (Potchefstroom Campus), Private Bag X 6001, Potchefstroom 2520, South Africa. Electronic address: guilermorubeno@blanquerna.url.edu.
³ Department of Physiological Sciences II, School of Medicine, University of Barcelona, Feixa Llarga Street, L'Hospitalet del Llobregat 08907, Spain. Electronic address: cjavierre@ub.edu.
⁴ FPCEE-Blanquerna, University Ramon Llull, c/ Cister 34, Barcelona 08022, Spain. Electronic address: jesusfg@blanquerna.url.edu.
⁵ FPCEE-Blanquerna, University Ramon Llull, c/ Cister 34, Barcelona 08022, Spain. Electronic address: silviabl0@blanquerna.url.edu.
⁶ Department of Physiological Sciences II, School of Medicine, University of Barcelona, Feixa Llarga Street, L'Hospitalet del Llobregat 08907, Spain. Electronic address: oninomen9@alumnes.ub.edu.
⁷ Department of Physiological Sciences II, School of Medicine, University of Barcelona, Feixa Llarga Street, L'Hospitalet del Llobregat 08907, Spain. Electronic address: jalamopi7@alumnes.ub.ed.
⁸ Department of Kinesiology and Nutrition, University of Illinois at Chicago, 1919 West Taylor Street, Chicago, IL 60612, USA. Electronic address: fernhall@uic.edu.

PMID: 26426514
DOI: 10.1016/j.ridd.2015.09.011

Abstract

Introduction: Adults with intellectual disabilities (ID) have significantly lower rates of physical activity and fitness than adults without ID. The 6-min walk test (6 MWT) is an inexpensive and simple way to test mobility and submaximal work capacity.

Purpose: To evaluate the test-retest reliability and validity of the 6 MWT in adults and seniors with ID and explore factors contributing to the 6 MWT distance (6 MWD).

Methods: 46 participants with mild, moderate and severe ID levels (age=41 ± 11 years) performed the 6 MWT three times (T1; T2; T3) to determine test-retest reliability. To test validity, peak oxygen uptake (VO2 peak) was measured using a treadmill protocol. To analyze factors contributing to the 6 MWD, sex, height, fat mass % and fat free mass %, ID level, isometric leg strength and relative VO2 peak were also measured.

Results: The walking distances for T1, T2 and T3 were 460.3 ± 76.9; 489.4 ± 81.2 and 491.4 ± 77.9 m, respectively. The 6 MWDs between T1-T2 and T1-T3 were significantly different (p<0.001), but T2 and T3 were not different. The intraclass correlation coefficient between T2 and T3 was 0.96 indicating high reliability. Relative VO2 peak and isometric leg strength significantly contributed to the 6 MWD (R(2)=0.55).

Conclusions: The 6 MWT is an easy, inexpensive, reliable and valid test in adults and seniors with ID. Familiarization is necessary to obtain reliable values. Relative VO2 peak and leg strength have significant impact on the distance walked.

Keywords: Adults; Intellectual disability; Reliability; Seniors; Six-minute walk test; Validity.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Aged
Exercise Test*
Female
Humans
Intellectual Disability*
Isometric Contraction
Male
Middle Aged
Muscle Strength*
Oxygen Consumption*
Physical Fitness*
Reproducibility of Results
Young Adult