| Authors (year of publication) [Reference] Location | Aim
Definition of caregiver burden | Sample (relationship) | Statistical analyses*
Reported sub-scores or single items of the outcome measures (Yes/No) | Key findings related to caregiver burden |
| Kudlicka et al. (2014) [66] United Kingdom | To evaluate how executive functions contribute to caregiver burden, as well as QoL and subjective health status of non-demented and non-depressed people with early-stage PD
No definition | 50 caregivers (45 spouses, 3 parents 7 children, 2 friends) | Multiple regression analysis
No | Caregiver burden was best explained by caregiver rated executive function of the PD patient, followed by disease severity |
| Carod-Artal et al. (2013) [61] Brazil | To analyse the main determinants of burden and HRQoL in Brazilian PD patients
No definition | 50 caregivers (39 spouses, 7 children, 4 others) | Multiple regression
Yes | The patient variables sleep disorders and behavioural psychotic symptoms were independent predictors of caregiver burden |
| Oguh et al. (2013) [65] USA | To determine what measures of PD disability, demographics and patient QoL are associated with caregiver strain
No definition | 2476 caregivers (91% spouses/partners, 9.4% other relatives, 0.5% other non-paid caregivers) | Multiple logistic regression
No | Patient quality of life impairment, male sex, disease severity, presence of concomitant medications and decreased verbal fluency were factors that predicted the likelihood of high caregiver strain |
| Tanji et al. (2013) [54] Japan and USA | To compare caregiver strain in spouses in one region of Japan and one in the US and examine the correlation between caregiver strain and patient/spousal variables
No definition | 178 caregivers (Spouses) | Spearman’s rho t-test Multivariate regression analysis
Yes | Spouses in the Japanese group reported more physical, time and financial caregiver strain. The US group reported more emotional strain. Falls was the most predictive patient variable for caregiver strain in the Japanese group. In the US group, patient depression was the most predictive variable for caregiver strain |
| Agrawal et al. (2012) [35] India | To find various predictors of caregiver burden in caregivers of persons with PD in India
“The physical, mental and socioeconomic problems experienced by the caregivers of chronic disease patients” (p. 59) | 91 caregivers (45 spouses, 32 children, 7 siblings, 7 others) | Linear regression
No | Patient depression scores were the best predictor of increased caregiver burden, followed by patient motor scores and the presence of sleep disturbances |
| Kelly et al. (2012) [12] Australia | To consider the relationship between HRQoL in non-demented PwPD and their caregivers and to determine the associations between caregiver and patient HRQoL and caregiver strain
“An enduring change … in caregiver’s fabric of well-being” (p. 2) | 97 caregivers (84% spouses, 13 % children, 3% others) | Spearman’s rho
No | Correlation was found between caregiver strain and the HRQoL of the person with PD |
| Leroi et al. (2012) [49] United Kingdom | To compare quality of life, level of disability and caregiver burden among PwPD with mild cognitive impairment (PD-MCI), PwPD with dementia (PDD), and PwPD with no cognitive impairment (PD-NC)
No definition | 102 caregivers (55 spouses, 47 adult children) | Analysis of covariance Analysis of variance
No | Caregiver burden as assessed by the ZBI was significantly greater in the PDD group compared to the two groups without dementia when adjusted for age and motor symptom severity. No significant difference in caregiver distress was observed between the three PD caregiver groups assessed by the NPI-CD |