Environmental aspects
Objective aspects of home
Based on the notion of P-E fit [
16], objective aspects of the home are operationalized as the number and type of physical environmental barriers in the home and the exterior surroundings, and the magnitude of accessibility problems, according to the Housing Enabler (HE) [
33]. With this instrument [
33,
34] administered in three steps, physical environmental barriers are objectively assessed based on national standards for housing design and juxtaposed with the individual profile of functional limitations:
Step 1) Interview and observation of functional limitations (12 items) and dependence on mobility devices (2 items): difficulty in interpreting information; visual impairment; blindness; loss of hearing; poor balance; incoordination; limitations of stamina; difficulties in moving head; reduced upper extremity function; reduced fine motor skill; loss of upper extremity skills; reduced spine and/or lower extremity function, and dependence on walking aids/wheelchair. All items are dichotomously assessed (Present/Not present). Step 1 renders a profile of functional limitations and provides a sum score of the number of functional limitations (range = 0–12). The data collected under Step 1 of the HE can also be used as a health aspect variable.
Step 2) Observation and dichotomous assessment (Present/Not present) of 161 physical environmental barriers indoors in the home (n=87), at entrances (n=46) and in the immediate exterior surroundings (n=28). Environmental barriers are objectively judged in relation to the applicable national standards for housing design. This step does not require any involvement of the participant. Step 2 generates the sum score variable ‘number of environmental barriers’ (range 0–161, or divided into the sub-domains indoors, entrances, exterior surroundings) and also provides a detailed account of the type of environmental barriers present.
Step 3) Based on the results of steps 1 and 2, the extent and character of the accessibility problems are calculated by means of instrument-specific software providing total/sub-domain scores as well as a rank-based list of ‘weighted environmental barriers’. For each environmental barrier item, the instrument comprises predefined severity ratings, operationalized as points (0–4) that quantify the severity of the problems predicted to arise in the specific case. Thus, the variable accessibility is operationalized as the magnitude of accessibility (P-E fit) problems caused by the case-specific combination of functional limitations/dependence on mobility devices and environmental barriers; higher scores= more accessibility problems. That is, the total accessibility score of the HE represents a function of the individual’s functional limitations, dependence on mobility devices and physical environmental barriers in the home and the closest exterior surroundings. In cases with no functional limitations/dependence on mobility devices, the accessibility score is 0. The theoretical maximum score is 1,832.
Perceived aspects of home
Perceived aspects of home comprise four domains defined, operationalized and empirically tested as described in detail by Oswald et al. [
29].
Housing satisfaction is evaluated with the question “Are you happy with the condition of your home (e.g. structure, roof, ceilings, walls, any dampness etc.)?” The response categories (scored 1–5) are: “No, definitely not”; “No, not to full extent”; “Neither”; “Yes, to some extent”; “Yes, definitely”.
Usability relates to the degree to which the physical housing environment supports activity performance, and is evaluated with two sub-scales from the Usability in My Home Questionnaire (UIMH): activity aspects (4 items) and physical environmental aspects (6 items). Each item is scored from 1 to 5. Only the end points are defined; these differ between activity aspects (“Not at all suitable”-“Entirely suitable”) and physical environmental aspects (Not at all usable-Fully usable).
Meaning of home relates to how an individual reacts to and feels about his/her home
, and is evaluated with the Meaning of Home Questionnaire (MOH). It covers physical (7 items), behavioural (6 items), emotional (10 items) and social aspects (5 items). Each item is scored from 0 (“strongly disagree”) to 10 (“strongly agree”); only the end points are defined.
Housing-related control beliefs are assessed with the Housing-related Control Beliefs Questionnaire (HCQ). The two included subscales (“Powerful others”; “Chance”) target external control in relation to the home. External control in relation to the home means that “some other person, luck, chance or fate is perceived as explanatory factors for what happens” [
29]. Both subscales have 8 items with five response categories (scored 1–5; higher= more external control).
In addition to these four domains, one question targets
neighborhood attachment (“Are you rooted and feel a strong affinity to your residential area?”) which has four response categories (scored 1 to 4; higher= less rooted) [
35]. Another set of questions target
housing adaptations, regarding the participant’s knowledge about the housing adaptation grant provided by Swedish municipalities as well as whether he/she has been provided such support (Yes/No). In cases where housing adaptations have been accomplished, locations as well as the form for financing the adaptations are to be specified. In addition, the participant is asked about whether he/she thinks that the housing adaptations made have had any impact on daily activities, dependence on help of others and the ability to remain living in the present dwelling. Additional response options are: “small/no effect”, “the situation has worsened” and “other”; to be specified. In relation to the potential impact, several response options may be given.
Use and need of assistive devices
Structured questions based on the ISO classification [
36] are used to register the use and need of ADs. The interviewer poses the following questions: “Which of the following ADs do you have, and which of them do you use? Are there any ADs which you need but do not have?” This part includes 33 predefined AD items: optical aids (3 items), hearing aids (3 items), mobility devices indoors (6 items) and outdoors (8 items), aids for daily activities (6 items) and other ADs (7 items) such as stair lift and visual door entry system. In addition, the participant can describe the use/need of additional products. A subsequent dichotomous (Yes/No) question specifically targets whether the participant has a security alarm.
Social support is explicitly addressed by the following question: “Is there someone around, who could assist you in case you would need some help and support?” If responding yes, the relationship to that person is to be specified.
Health aspects
The battery of self-administered questions and questionnaires provided by post is initiated by a self-rating of the current mobility as either Good (“on”); Good, but hyperkinetic; or Bad (“off”), followed by two dichotomous (Yes/No) questions that target fluctuations and dyskinesia. The subsequent self-ratings primarily target:
freezing of gait, walking difficulties, fear of falling, activity avoidance due to a risk of falling, non-motor symptoms, fatigue, general self-efficacy and activities of daily living. The following questionnaires are included (Table
1): the self-administered version [
28] of the Freezing of Gait Questionnaire [
37] (FOG-Qsa); the generic Walk-12 (Walk-12G) [
24]; Falls Efficacy Scale-International (FES-I) [
38]; modified Survey of Activities and Fear of Falling in the Elderly (mSAFFE) [
25,
39]; the Nonmotor Symptoms Questionnaire (NMSQuest) [
26]; the Energy section of the Nottingham Health Profile (NHP-EN) [
27]; the General Self-Efficacy Scale (GSE) [
40]; and the Parkinson’s Disease Activities of Daily Living Scale (PADLS) [
23]. Six additional dichotomous (Yes/No) questions concern
perceived balance problems including near falls: unsteadiness while walking; dual tasking (“Do you experience balance problems while standing or walking when doing more than one thing at a time, e.g. carrying a tray while walking?”); unsteadiness while turning; fear of falling; activity avoidance due to a risk of falling; and whether the participant has experienced any near falls during the past six months (if yes, the approximate number of times should be specified). A near fall is defined as “a fall initiated but arrested by support from a wall, railing, other person, etc.” [
41].
Dizziness is screened for by the question: “Have you ever experienced any dizziness in the past year?” If answering ‘yes’, the participant is asked to verify the sensation as: (i) rotational/spinning; (ii) lightheadedness; (iii) other or (iv) don’t know [
42]. Several options may be ticked. A single item question (scored 1–5; higher = worse) targets perceived
general health; inspired by the general health question in the Medical Outcome Study (MOS) 36-item Short-Form health survey [
43]. The final question in the self-administered battery concerns whether the participant responded independently or attained assistance.
At the subsequent home visit, initially the participant is asked to verify the time point of the latest intake of anti-PD medications, and to self-rate his/her present state of mobility (see above).
Motor symptoms are assessed according to the Unified Parkinson’s Disease Rating Scale (UPDRS, part III) (14 items) [
44], in which item no. 30 specifically captures the postural response in relation to an external perturbation (scored 0–4). The total score of the UPDRS part III ranges from 0–108 points (higher scores = worse).
Complications of therapy in the past week (e.g. dyskinesias, fluctuations) are assessed according to the UPDRS part IV (11 items) [
44]. The
severity of PD is assessed according to the Hoehn & Yahr staging scale [
45] (ranges from I to V; higher = worse), both for the on and off condition although the latter is based on anamnestic information.
Cognitive functions are assessed with the Montreal Cognitive Assessment (MoCA) (max. score = 30) [
46]. Two
timed tests target mobility and lower-extremity function, respectively; the Timed Up & Go (three trials) [
47,
48]) and the Chair-Stand Test (one trial) [
49,
50]. Details about the standardizations of these two tests are provided by Nilsson et al. [
51].
Pain is assessed by the dichotomous (Yes/No) question “Are you bothered by pain?” If responding yes, the severity subscale of the brief screening version of the Multidimensional Pain Inventory (Swedish version) is used [
52]. It consists of two items (each scored 0–6; higher = more severe pain). Locations of pain are also to be specified.
Falls are targeted by several structured questions, applying the European consensus definition of a fall [
53]. Initially, the participant is asked a dichotomous (Yes/No) question regarding falls during the past year. If responding yes, a subsequent question concerns whether it happened more than once (Yes/No) including an estimate of how many times. In addition, 13 predefined locations of falls (indoors and outdoors) are to be specified and ranked (1= most common location). One question concerns whether any fall incident required medical care, and the final question targets the occurrence and number of falls during the past six months.
The structured interview during the home visit also targets
psychological wellbeing, coping, life satisfaction and depression. The used version of the Psychological Wellbeing Questionnaire (PWQ) [
54] consists of 19 statements whereas the Coping Pattern Schedule (CPS) has 13 [
55]. Both scales have the same response categories (scored 1–5): “strongly disagree”; “disagree”; “neutral”; “agree”; and “strongly agree”. Life satisfaction is evaluated by item 1 (scored 1–6; higher = better) of the Life Satisfaction Questionnaire (LISAT-11) [
56]. Depressive symptoms are assessed with the Geriatric Depression Scale (GDS-15) [
57]. It consists of 15 dichotomous (Yes/No) items that add to a total score (range 0–15; higher = more depressive symptoms).
Independence in activities of daily living (ADL) is assessed by means of observation and interview according to the ADL Staircase [
58]. Each of the nine items included (i.e. activities) is rated as independent/partly dependent/dependent. For ADL items rated as “independent”, the interviewer asks a dichotomous (Yes/No) question [
59]: “Even if you manage on your own, do you experience any difficulty when performing…?” In addition,
perceived functional independence (PFI) is addressed by the question “All in all, how would you evaluate your own independence, i.e. in performing activities of daily living?” It is scored from 0 (“completely dependent”) to 10 (“completely independent”); only the endpoints are defined.
Participation in life situations is captured by structured questions representing two dimensions; ‘performance-oriented participation’ and ‘togetherness-oriented participation’ [
60]. Fifteen questions address the frequency of participating in different social activities. Each of the 15 items has five response categories: “Every day”; “Once/twice a week”; “Once/twice a month”; “Once/twice a year”; and “Nearly never/never”. An additional dichotomous question (Yes/No) addresses membership of any association and if so, whether the individual participates in its organized activities. A similar question specifically targets this in relation to patient associations. Furthermore, the participant is asked to specify three leisure activities (indoors and outdoors, respectively) that he/she likes to do nowadays, whether these activities are performed alone and/or with others, and if there are unmet wishes or barriers in relation to performance. One additional question concerns the frequency of outdoor walks, with five response categories: “Every day”; “Once/twice a week”; “Once/twice a month”; “Nearly never”; and “Never”. Finally, the participant is asked whether he/she has used any activity center services for senior citizens during the latest 12 months.
At the end of the home visit, the participant is asked whether he/she is interested in participating in future follow-ups. After the home visit, the project administrator registers whether any other person participated during the home visit, and if so, in what way and whether it was perceived as influencing the responses of the participant (scored 0–10; higher scores= more impact). The project administrator also registers perceived communication ability (scored 0–10; higher= better) and reliability of responses (scored 1–5; higher= worse).