Article

Evaluation of the Environmental Bias on Accelerometer-Measured Total Daily Activity Counts and Owner Survey Responses in Dogs with Osteoarthritis

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  • Veterinary Specialty Hospital - North County
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Abstract

Objective To determine if environmental variables affect the average daily activity counts (AC) of dogs with osteoarthritis (OA) and/or owners' perception of their dog's clinical signs or quality of life. Methods The AC and Canine Brief Pain Inventory (CBPI) owner questionnaires of 62 dogs with OA were compared with daily environmental variables including the following: average temperature (°C), high temperature (°C), low temperature (°C), relative humidity (%), total precipitation (mm), average barometric pressure (hPa) and total daylight hours. Results Daily AC significantly correlated with average temperature and total daylight hours, but average temperature and total daylight hours accounted for less than 1% of variation in AC. No other significant relationships were found between daily AC and daily high temperature, low temperature, relative humidity, total precipitation or average barometric pressure. No statistical relationship was found between daily AC and the CBPI, nor between environmental variables and the CBPI. Canine Brief Pain Inventory scores for pain severity and pain interference decreased significantly over the test period. Clinical Significance The relationship between daily AC and average temperature and total daylight hours was significant, but unlikely to be clinically significant. Thus, environmental variables do not appear to have a clinically relevant bias on AC or owner CBPI questionnaires. The decrease over time in CBPI pain severity and pain interference values suggests owners completing the CBPI in this study were influenced by a caregiver placebo effect.

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... The ability to return to work based on owner surveys was used in the three equine osteopathic studies [20][21][22]. While owner reports may be useful for global assessments of health or performance, they are limited in quantifying the presence, localization and severity of pain, stiffness or muscle hypertonicity [69,70]. Unfortunately, there are very few validated functional questionnaires or standardized owner surveys in veterinary medicine that have been designed to capture measures of musculoskeletal function and specific responses to applied therapies [47,71]. ...
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... An increase in 20% of weekly AC has been observed in dogs receiving NSAID therapy for OA compared with placebo [26]. While it has been described that the total amount of precipitation and daylight hours are unlikely to produce a clinically relevant change in activity data [29], that study did not evaluate other owner-induced factors that have been proposed to change daily AC such as availability to spend time with their dog and motivation to encourage activity [28]. We attempted to address some of the shortcomings of activity monitoring by measuring changes in the amount of sedentary time, light, moderate, and/or vigorous activity times [28]. ...
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Wet-bulb temperature and relative humidity from air temperature and dewpoint temperature
National Weather Service Weather Forecast Office. Wet-bulb temperature and relative humidity from air temperature and dewpoint temperature. 2013. Available at: http://www.srh. noaa.gov/images/epz/wxcalc/rhWetBulbFromTd.pdf; Accessed February 2016