Effects of the WHO 8-step wheelchair-service-delivery process on wheelchair users in El Salvador: a cohort study

Figures & data

Figure 1. Study flow diagram.

Study flow diagram explaining how study participants were screened for eligibility, enrolled, assessed for wheelchair provision and service delivery, and included for data analysis.

Figure 2. Study wheelchairs. From left to right: a) standard, b) active, and c) all-terrain wheelchairs.

Photos of the three wheelchairs provided in the study, from left to right: standard wheelchair, active wheelchair, and all-terrain wheelchair.

Table 1. Questionnaires administered by study visit and participant type.

	Questionnaire	Baseline	Delivery	3-Month	6-Month
Wheelchair users	ISWP Minimum Uniform Dataset (MUD) Part 1, Part 2^a	✓	–	✓	✓
	Wheelchair Skills Test Questionnaire (WST-Q) ^a	✓	–	✓	✓
	Wheelchair Maintenance Training Questionnaire (WMT-Q) ^a	✓	–	✓	✓
	Breakdowns and Adverse Consequences Questionnaire (BAC-Q) ^a	✓	✓	✓	✓
	Poverty Probability Index (PPI) for El Salvador	✓	–	–	✓
	WHO Quality of Life Questionnaire (WHOQOL-BREF)	✓	–	–	✓
	MIT Wheelchair-related Health Questionnaire ^a	✓	✓	✓	✓
	Data Loggers ^a	✓	✓	✓	–
Caregivers	Assistance with ADLs Questionnaire	✓	–	✓	✓
	Zarit Burden Interview (ZBI-12)	✓	–	✓	✓

^aQuestionnaire only delivered at baseline if the participant had a wheelchair.

Table 2. Demographic and clinical data.

Wheelchair Users (n = 247)
Had a wheelchair at baseline, n (%)	175 (71%)
Sex, n (%)
Female	93 (38%)
Male	154 (62%)
Age in years, mean (SD)
All participants	54.9 (19.7)
Females	62.7 (19.7)
Males	50.1 (18.1)
Standard wheelchair recipients	66.2 (17.7)^a
Active wheelchair recipients	41.3 (15.1)^a
All-terrain wheelchair recipients	56 (15.4)^a
Live with spouse, n (%)
No	137 (55%)
Yes	110 (45%)
Education level, n (%)
None	45 (18%)
Primary school (first to third grade)	36 (15%)
Primary school (fourth to sixth grade)	35 (15%)
Primary school (seventh to ninth grade)	45 (18%)
High school (incomplete)	5 (2%)
High school (complete)	44 (18%)
Technical education (incomplete)	1 (0%)
Technical education (complete)	7 (3%)
College (incomplete)	10 (4%)
College (complete)	17 (7%)
Postgraduate education	2 (1%)
Employment status, n (%)
Unemployed	140 (57%)
Student	7 (3%)
Homemaker/full-time parent	34 (14%)
Self-employed part-time	18 (7%)
Self-employed full-time	16 (6%)
Employed part-time	3 (1%)
Employed full-time	29 (12%)
Medical condition, n (%)
Spinal cord injury	76 (31%)
Amputation	64 (26%)
Aging/Weakness	17 (7%)
Rheumatoid arthritis	13 (5%)
Stroke	12 (5%)
Spina Bifida	12 (5%)
Injury	12 (5%)
Consequences of Polio	11 (4%)
Brain injury	9 (4%)
Cerebral Palsy	9 (4%)
Other conditions	12 (5%)

^aSignificant differences in age at p < 0.05 found for participants when grouped by wheelchair type using independent ANOVA and t-tests.

Table 3. Demographic data at baseline for caregivers.

Parameter	Value
Age^a in years, mean (SD)	50.8 (14.8)
Sex^a, n (%)
Females	54 (73%)
Males	20 (27%)
Occupational status^b, n (%)
Unemployed	21 (17.6%)
Student	1 (0.8%)
Homemakers or full-time parents	43 (36.1%)
Self-employed or employed, part- or full time	54 (45.5%)
Paid work^b, n (%)
Have a paid work	50 (42%)
Receive payment as caregiver	4 (3.4%)
Hours of care provided per week^b, n (%)
Zero	1 (0.8%)
Less than 10 h per week	6 (5%)
Between 10 and 20 h per week	9 (7.6%)
Between 20 and 40 h per week	16 (13.4%)
Between 40 and 60 h per week	20 (16.8%)
Between 60 and 80 h per week	14 (11.8%)
More than 80 h per week	58 (44.5%)

^aCollected at the 3-month follow-up visit, n = 74.

^bCollected at baseline, n = 119.

Table 4. Wheelchair-related health indicators over time, n (%).

Measure	Baseline n = 247	Delivery n = 165	3-Month n = 197	6-Month n = 170	p Values^d
Pressure injuries^a^,^b, n(%)	30 (12%)	8 (5%)^e	13 (6%)	8 (5%)	0.001
Falls during wheelchair transfer^b^,^c, n(%)	56 (32%)	24 (15%)^e	11 (6%)^e	12 (7%)^e	0.001
Falls during wheelchair riding^b^,^c, n(%)	36 (21%)	11 (7%)^e	14 (7%)^e	10 (6%)^e	0.001
Upper extremity injury or pain^b^,^c, n(%)	42 (24%)	24 (15%)	24 (12%)^e	16 (10%)^e	0.004
Hand injury or pain^b^,^c, n(%)	40 (23%)	19 (12%)	22 (11%)	8 (5%)^e	0.001
Back pain^b^,^c, n(%)	101 (58%)	63 (38%)^e	38 (19%)^e^,f	32 (19%)^e^,f	0.001

^aQuestion asked to all wheelchair users in the study.

^bIn the prior 3 months.

^cQuestion asked to participants only if had a wheelchair at baseline, n = 175.

^dp-values for all group comparisons in the same row are the same unless a ‘greater than’ or ‘less than’ symbol is indicated.

^eSignificant difference found when compared with baseline data.

^fSignificant difference found when compared with delivery data.

Table 5. Mean (SD) quality of life scores by time as measured with WHO QOL-Bref (n = 164).

Measure	Baseline	6-Month	p Values
Quality of Life (WHO QOL-BREF)^a, mean (SD)
Overall quality of life^b	2.7 (1.2)	3.3 (1.3)^d	0.001
Satisfaction with health^b	2.7 (1.2)	3.2 (1.0)^d	0.001
Physical Domain^c	11.9 (3.2)	13.3 (3.2)^d	0.001
Psychological Domain^c	13.1 (3.7)	13.3 (4.5)	0.473
Social Relationships Domain^c	15.0 (3.7)	14.4 (4.8)	0.116
Environment Domain^c	11.9 (2.5)	13.0 (2.6)^d	0.001

^aIncludes all wheelchair users in the study.

^bScore range: 1 to 5.

^cScore range: 4 to 20.

^dSignificant difference found when compared with baseline data.

Table 6. Median (IQR) total percentage WST-Q capacity scores by time and by wheelchair ownership at baseline.

Measure	Baseline	3-Month		6-Month		p Values^b
	Had a wheelchair previously n = 175	Had a wheelchair previously n = 139	Did not have a wheelchair previously n = 58	Had a wheelchair previously n = 125	Did not have a wheelchair previously n = 45
WST-Q Capacity score, median (IQR)	45.2 (40.3)	59.7(37.1)	36.3 (44.8)^a	51.6 (38.7)	32.3 (48.4)^a	0.001

^aSignificant difference found from users who had a wheelchair previously, at the same time point.

^bP-values for all group comparisons in the same row are the same unless a ‘greater than’ or ‘less than’ symbol is indicated.

Table 7. Wheelchair use measurements by time, median (IQR).

Measure	Baseline	Delivery		3-Month		P Values^b
	Had a wheelchair previously n = 136	Had a wheelchair previously n = 118	Did not have a wheelchair previously n = 88	Had a wheelchair previously n = 104	Did not have a wheelchair previously n = 67
Average daily distance (m/day), median (IQR)	248.3 (470.9)	106.0 (326.7)^a	78.8 (195.5)	109.7 (370.1)^a	59.7 (213.9)	<0.004
Average daily speed (m/s), median (IQR)	0.27 (0.30)	0.24 (0.25)^a	0.23 (0.27)	0.24 (0.30)^a	0.24 (0.26)	<0.024
Average days data was collected, median (IQR)	21.1 (23.1)	22.1 (18.2)	20.9 (14.1)	23.9 (15.4)	26.9 (13.2)	>0.311

^aSignificant difference found when compared with baseline data.

^bP-values for all group comparisons in the same row are the same unless a ‘greater than’ or ‘less than’ symbol is indicated.

Table 8. Number (%) of participants who did wheelchair repairs and who experienced adverse events by time and by wheelchair ownership at baseline.

Measure	Baseline	Delivery		3-Month		6-Month
	Had a wheelchair previously n = 175	Had a wheelchair previously n = 147	Did not have a wheelchair previously n = 6	Had a wheelchair previously n = 139	Did not have a wheelchair previously n = 47	Had a wheelchair previously n = 120	Did not have a wheelchair previously n = 41
More than one wheelchair repair, n (%)	99 (56.6)	53 (36.1)	0 (0)	16 (11.5)^a	2 (4.3)^a	18 (15.0)^a	1 (2.4)^a
No wheelchair repairs done, n (%)	76 (43.4)	94 (63.9)	6 (100)	123 (88.5)	45 (95.7)	102 (85.0)	40 (97.6)

^aSignificant difference found when compared with baseline and delivery data at p = 0.001.

Table 9. Burden of care indicators for caregivers over time, median (IQR).

Measure	Baseline n = 112	3-Month n = 74	6-Month n = 43	p Values^b
Caregiver burden (ZBI-12)^a, median (IQR)	11.0 (11.0)	8.5 (9.0)	10.0 (11.3)	0.492
Number of ADL per assistance level, median (IQR)
No assistance	6 (6)	9 (5)^c	8 (8)	0.001
Some assistance	3 (3)	3 (3)	2.5 (6)	0.351
Complete assistance	5 (5)	2 (3)^c	1 (3)^c	<0.009

^aScore range: 0 to 48. The higher the score, the greater the burden of care.

^bP-values for all group comparisons in the same row are the same unless a ‘greater than’ or ‘less than’ symbol is indicated.

^cSignificant difference found when compared with baseline data.

Table 10. Mean (SD) poverty probabilities by time (n = 162).

Measure	Baseline	6-Month	p-values
Poverty Probability Index (PPI)^a, mean (SD)
Below National poverty line	25.6 (19.6)	21.8 (18.4)^b	0.004
Below USAID “Extreme” poverty line	9.0 (10.3)	7.1 (10.5)^b	0.012

^aIncludes all wheelchair users in the study.

^bSignificant difference found when compared with baseline data.

Data availability statement

All data files of this study are publicly available from the OPEN-ICPSR (Inter-university Consortium for Political and Social Research) database at https://doi.org/10.3886/E173201V1.