Background

The Parkinson's Disease (PD) Home Diary (HD) is a common clinical outcome measure, but studies show only fair agreement between clinical observer and patient assessments, with no significant improvement after patient training.

Objectives

To investigate the agreement between a clinical observer and relatives of PD patients when assessing the patient's motor status in the HD. Agreement was also assessed for relative-patient and patient-observer pairs.

Methods

This observational study included 28 PD patients with motor fluctuations and their relatives. It involved a screening visit with structured training on motor fluctuations and one day of motor ratings, where the observer, relative, and patient independently assessed the patient's motor state in the HD half-hourly.

Results

Observer, patient, and relative triads completed 445 HD assessment sets. Temporal agreement was fair for observer-relatives (Cohen's κ = 0.250) and relatives-patients (κ = 0.230), but slight for patients-observer (κ = 0.120). For observer-relatives, agreement was highest for “On without dyskinesia” (71%), and lowest for “Off” (26%). Daily time distributions differed significantly between relatives and the clinical observer for “Off” (p = 0.006) and “On without dyskinesia” (p = 0.012), but not for “On with dyskinesia” (p = 1.000).

Conclusions

This study reports fair temporal agreement of motor state assessments between relatives-observer and relatives-patients, with slight agreement between patients-observer. Relatives’ assessments of daily time in different motor states showed significant differences from the clinical observer assessments. This further highlights the challenges in obtaining reliable motor status data and the need for further research into objective assessment methods.

Plain language summary

Comparing how relatives of Parkinson patients and doctors rate Parkinson's motor states

Purpose?

Parkinson's disease patients often develop motor fluctuations, switching between feeling well (“On”), feeling worse (“Off”), and having involuntary movements (“On with dyskinesia”). To track these fluctuations, patients often use a Home Diary to record their motor state every 30 min. The diary is widely used both in clinical care and in research. However, previous studies show that patients and healthcare professionals often disagree when simultaneously assessing the patients motor state in the diary. This can lead to incorrect treatment decisions or misleading study results. Since relatives of Parkinson patients may notice the patients’ symptoms differently, involving them might give a more accurate view of the patient's condition.

The study aimed to find out how well clinicians and relatives agree when rating the patient's motor state using the Home Diary. It also investigated how patients agree with clinicians and relatives.

How?

The study included 28 Parkinson's patients and their relatives. First, they attended a screening visit where they also participated in an education about motor fluctuations. Next, they spent a full day (8:30 AM–4:00 PM) at the clinic. During this time, the patient, their relative, and the clinician independently recorded the patient's motor state every 30 min using the Home Diary.

Findings?

Clinicians and relatives agreed on the patient's motor state 52% of the assessments. Agreement was highest for “On without dyskinesia” (71%), followed by “On with dyskinesia” (52%). However, they only agreed on the “Off” state in 26% of cases. Relatives and patients agreed 56% of the time, while patients and clinicians agreed 44% of the time.

Meaning?

The study shows that agreement on motor state ratings is low between clinician, patients, and relatives. This highlights the difficulty of obtaining reliable information about Parkinson patients’ motor fluctuations and the need for more reliable ways to assess them.