title: Validity of activity monitors in health and chronic disease: a systematic review.
abstract: The assessment of physical activity in healthy populations and in those with chronic diseases is challenging. The aim of this systematic review was to identify whether available activity monitors (AM) have been appropriately validated for use in assessing physical activity in these groups. Following a systematic literature search we found 134 papers meeting the inclusion criteria; 40 conducted in a field setting (validation against doubly labelled water), 86 in a laboratory setting (validation against a metabolic cart, metabolic chamber) and 8 in a field and laboratory setting. Correlation coefficients between AM outcomes and energy expenditure (EE) by the criterion method (doubly labelled water and metabolic cart/chamber) and percentage mean differences between EE estimation from the monitor and EE measurement by the criterion method were extracted. Random-effects meta-analyses were performed to pool the results across studies where possible. Types of devices were compared using meta-regression analyses. Most validation studies had been performed in healthy adults (n=118), with few carried out in patients with chronic diseases (n=16). For total EE, correlation coefficients were statistically significantly lower in uniaxial compared to multisensor devices. For active EE, correlations were slightly but not significantly lower in uniaxial compared to triaxial and multisensor devices. Uniaxial devices tended to underestimate TEE (-12.07 (95%CI; -18.28 to -5.85) %) compared to triaxial (-6.85 (95%CI; -18.20 to 4.49) %, p=0.37) and were statistically significantly less accurate than multisensor devices (-3.64 (95%CI; -8.97 to 1.70) %, p<0.001). TEE was underestimated during slow walking speeds in 69% of the lab validation studies compared to 37%, 30% and 37% of the studies during intermediate, fast walking speed and running, respectively. The high level of heterogeneity in the validation studies is only partly explained by the type of activity monitor and the activity monitor outcome. Triaxial and multisensor devices tend to be more valid monitors. Since activity monitors are less accurate at slow walking speeds and information about validated activity monitors in chronic disease populations is lacking, proper validation studies in these populations are needed prior to their inclusion in clinical trials.
authors: Faculty of Kinesiology and Rehabilitation Sciences, Department of Rehabilitation Sciences, Katholieke Universiteit Leuven, Leuven, Belgium.
authors: Hans
authors: H
authors: Van Remoortel
authors: Santiago
authors: S
authors: Giavedoni
authors: Yogini
authors: Y
authors: Raste
authors: Chris
authors: C
authors: Burtin
authors: Zafeiris
authors: Z
authors: Louvaris
authors: Elena
authors: E
authors: Gimeno-Santos
authors: Daniel
authors: D
authors: Langer
authors: Alastair
authors: A
authors: Glendenning
authors: Nicholas S
authors: NS
authors: Hopkinson
authors: Ioannis
authors: I
authors: Vogiatzis
authors: Barry T
authors: BT
authors: Peterson
authors: Frederick
authors: F
authors: Wilson
authors: Bridget
authors: B
authors: Mann
authors: Roberto
authors: R
authors: Rabinovich
authors: Milo A
authors: MA
authors: Puhan
authors: Thierry
authors: T
authors: Troosters
mesh_terms: D002908:Chronic Disease; D016208:Databases, Factual; D004734:Energy Metabolism; D005080:Exercise Test / Q000295:instrumentation / Q000379:methods; D006801:Humans; D008991:Monitoring, Physiologic / Q000295:instrumentation* / Q000379:methods*; D009043:Motor Activity; D012420:Running