Table 2 Agreement between graders identifying home hazards: Krippendorff’s alpha (n = 20 homes)

Handrails

Number of handrails

E, S

2

0.89 (0.75–0.97)

0.91 (0.00–0.91)

0.82 (0.00–0.91)

0.92 (0.00–0.92)

Handrail perimeter <4 inches or >6.25 inches

E, S

2

0.77 (0.57–0.92)

0.78 (0.00–0.89)

0.86 (0.00–0.86)

0.64 (0.00–0.88)

Loose handrails

E, S

2

0.75 (0.37–0.94)

0.84 (0.00–0.84)

0.62 (0.00–0.81)

0.78 (0.00–0.78)

Portion of stairs without handrail

E, S

2

0.64 (0.46–0.79)

0.66 (0.32–0.92)

0.77 (0.00–0.92)

0.52 (0.13–0.90)

No grab bars in tub/shower

BA

1

0.58 (0.37–0.79)

0.44 (0.00–0.78)

0.90 (0.00–0.90)

0.36 (−0.07–0.79)

No grab bars at toilet

BA

1

0.49 (0.16–0.81)

0.46 (−0.35–0.73)

0.49 (−0.01–0.83)

0.49 (−0.01–0.83)

No grab bars at sink

BA

1

0.09 (−0.46–0.55)

−0.03 (−1.00–0.49)

0.33 (−0.56–0.78)

−0.11 (−1.00–0.55)

Height of handrail <34 inches or >38 inches

E, S

2

0.00 (N/A)

0.00 (N/A)

0.00 (N/A)

0.00 (N/A)

No contrast between handrails and walls

S

1

−0.05 (−0.93–0.65)

0.00 (−1.00–0.00)

−0.04 (−1.00–0.48)

−0.09 (−1.00–0.64)

Floor

Cracked external steps

E

1

1.00 (0.00–0.00)

1.00 (0.00–0.00)

1.00 (0.00–0.00)

1.00 (0.00–0.00)

Height of front step riser <4 inches or >7.75 inches

E

1

0.87 (0.00–0.94)

0.81 (0.00–0.81)

1.00 (0.00–0.00)

0.81 (0.00–0.81)

Width of stairway <36 inches

E, S

2

0.81 (0.69–0.93)

0.85 (0.00–0.93)

0.85 (0.00–0.93)

0.70 (0.32–0.93)

Width of hallway <36 inches

H

1

0.79 (0.61–0.93)

0.68 (0.00–0.89)

1.00 (0.00–0.00)

0.68 (0.00–0.89)

Sloping external steps

E

1

0.78 (0.00–0.89)

1.00 (0.00–0.00)

0.64 (−0.09–0.64)

0.64 (−0.09–0.64)

Width of doorway <32 inches or >48 inches

E

1

0.78 (0.60–0.93)

0.68 (0.00–0.89)

1.00 (0.00–0.00)

0.68 (0.00–0.89)

Frayed/torn/folded carpeting

BA, BR, D, H, K, L

6

0.76 (0.56–0.92)

0.71 (0.00–0.85)

0.71 (0.00–0.85)

0.76 (0.00–0.88)

Height of door threshold >0.5 inches

BA, BR, D, E, H, K, L

7

0.73 (0.59–0.86)

0.82 (0.63–0.96)

0.73 (0.52–0.90)

0.77 (0.58–0.92)

Loose external steps

E

1

0.73 (0.00–0.87)

0.64 (−0.08–0.64)

1.00 (0.00–0.00)

0.64 (−0.09–0.64)

Landing more narrow than doorway

E

1

0.72 (0.00–0.86)

1.00 (0.00–0.00)

0.63 (−0.12–0.63)

0.63 (−0.12–0.63)

Unsecured rugs; rugs with curling edges

BA, BR, D, H, K, L

6

0.68 (0.53–0.82)

0.89 (0.00–0.95)

0.64 (0.39–0.85)

0.58 (0.31–0.84)

Glossy or shiny finish

BA, BR, D, H, K, L, S

7

0.65 (0.37–0.86)

0.78 (0.61–0.92)

0.48 (0.15–0.77)

0.66 (0.38–0.89)

Smooth finish (no traction)

E, S

2

0.65 (0.36–0.88)

0.67 (0.00–0.84)

0.40 (−0.20–0.80)

0.76 (0.00–0.76)

Sloped ground on public sidewalk

E

1

0.62 (0.38–0.86)

0.60 (0.00–0.87)

0.67 (0.00–0.84)

0.58 (0.00–0.86)

Floor covered with objects/cluttered (>50% clutter)

BA, BR, D, H, K, L

6

0.60 (0.00–0.86)

0.79 (0.00–0.88)

0.56 (0.00–0.84)

0.42 (−0.14–0.87)

Height of stair riser <4 inches or >7.75 inches

E, S

2

0.60 (0.40–0.78)

0.56 (0.26–0.85)

0.67 (0.35–0.92)

0.61 (0.30–0.84)

No contrast between door threshold and floor

BA, BR, D, H, K, L

6

0.60 (0.43–0.76)

0.70 (0.46–0.90)

0.56 (0.30–0.78)

0.61 (0.40–0.83)

Depth of stair treads <10 inches

E, S

2

0.57 (0.38–0.76)

0.45 (0.14–0.77)

0.53 (0.22–0.84)

0.72 (0.00–0.91)

No contrast between floors and fixtures

E, S

2

0.55 (0.33–0.78)

0.43 (−0.03–0.77)

0.46 (0.04–0.79)

0.73 (0.00–0.87)

Landing only on one side of doorway

E

1

0.54 (0.00–0.89)

0.63 (−0.111–0.63)

0.63 (−0.12–0.63)

0.63 (−0.12–0.63)

No non-skid rug/mat outside bathtub/shower

BA

1

0.53 (0.23–0.82)

0.45 (−0.37–0.73)

0.70 (0.00–0.85)

0.32 (−0.36–0.77)

Landing <36 inches

E

1

0.52 (0.21–0.76)

0.65 (0.00–0.83)

0.42 (−0.15–0.81)

0.62 (0.00–0.81)

No bathmat/non-skid strips in bathtub/shower

BA

1

0.45 (0.18–0.69)

0.53 (0.05–0.88)

0.54 (0.07–0.88)

0.21 (−0.32–0.74)

Uneven dirt path on public sidewalk

E

1

0.41 (0.04–0.78)

0.45 (−0.38–0.72)

0.30 (−0.39–0.77)

0.46 (−0.08–0.82)

Stair nosing >1.5 inches

E

1

0.48 (−0.29–0.74)

0.00 (−1.00–0.00)

0.00 (−1.00–0.00)

1.00 (0.00–0.00)

Cracked pavement on private path

E

1

0.46 (0.12–0.80)

0.18 (−0.43–0.80)

0.79 (0.00–0.79)

0.44 (−0.41–0.72)

Sloped ground on private path

E

1

0.46 (0.13–0.80)

1.00 (0.00–0.00)

0.13 (−0.53–0.78)

0.19 (−0.41–0.80)

Papers/books/towels/shoes/magazines/boxes/blankets/other objects in pathway

BA, BR, D, H, K, L, S

7

0.40 (0.09–0.67)

0.63 (0.31–0.88)

0.26 (−0.03–0.54)

0.39 (0.09–0.64)

Broken tiles

BA, BR, D, H, K, L

6

0.38 (−0.16–0.87)

−0.01 (−1.00–0.49)

0.48 (−0.31–0.74)

−0.02 (−1.00–0.49)

Exterior door swings over step with no landing

E

1

0.38 (0.01–0.69)

0.59 (−0.02–0.80)

0.11 (−0.59–0.65)

0.58 (−0.04–0.79)

No contrast between stair treads and risers

E, S

2

0.37 (−0.16–0.79)

0.00 (−1.00–0.00)

−0.02 (−1.00–0.49)

0.47 (−0.33–0.74)

Uneven dirt path on private path

E

1

0.34 (−0.21–0.78)

−0.04 (−1.00–0.48)

−0.12 (−1.00–0.63)

0.77 (0.00–0.77)

Cracked pavement on public sidewalk

E

1

0.32 (−0.08–0.66)

0.21 (−0.60–0.80)

0.45 (−0.10–0.82)

0.44 (−0.41–0.72)

Loose bricks or paver stones on public sidewalk

E

1

0.30 (−0.40–0.83)

0.00 (−1.00–0.00)

0.64 (−0.08–0.64)

−0.04 (−1.00–0.48)

Loose electrical/phone cords on floor

BA, BR, D, H, K, L

6

0.28 (−0.22–0.72)

−0.02 (−0.97–0.75)

0.50 (0.07–0.85)

0.09 (−0.49–0.59)

No contrast between floors and furniture/obstacles

BR, D, K, L

4

0.19 (−0.13–0.45)

0.18 (−0.13–0.48)

0.36 (0.04–0.68)

−0.14 (−0.61–0.33)

No contrast between stair treads

E, S

2

0.16 (−0.47–0.69)

0.00 (−1.00–0.00)

−0.06 (−1.00–0.74)

0.35 (−0.51–0.78)

Walkway narrowed by obstacles/furniture

BA, BR, D, K, L

5

0.15 (−0.64–0.82)

0.38 (−0.44–0.79)

−0.02 (−1.00–0.66)

0.00 (−1.00–0.00)

Blankets/sheets on floor

BR

1

0.09 (−0.46–0.54)

0.33 (−0.35–0.78)

−0.09 (−1.00–0.73)

−0.06 (−1.00–0.65)

Slippery floor (no traction with soled shoes)

BA, BR, D, H, K, L

6

0.01 (−0.37–0.34)

0.08 (−0.22–0.37)

−0.18 (−0.60–0.20)

0.11 (−0.46–0.64)

Carpet runners with curling edges

BA, BR, D, H, K, L

6

0.00 (−0.67–0.50)

0.00 (N/A)

0.00 (−1.00–0.00)

−0.29 (−1.00–0.57)

Interior door swings over step with no landing

E

1

0.00 (−1.00–0.50)

0.00 (−1.00–0.00)

0.00 (−1.00–0.00)

0.00 (N/A)

Loose/torn coverings on treads

S

1

0.00 (N/A)

0.00 (N/A)

0.00 (N/A)

0.00 (N/A)

Depth of front step tread <10 inches

E

1

0.00 (N/A)

0.00 (N/A)

0.00 (N/A)

0.00 (N/A)

Loose bricks or paver stones on private path

E

1

−0.02 (−1.00–0.74)

0.00 (N/A)

−0.06 (−1.00–0.47)

−0.04 (−1.00–0.48)

Lighting

Broken light fixture/missing bulbs

E, S

2

1.00 (0.00–0.00)

1.00 (0.00–0.00)

1.00 (0.00–0.00)

1.00 (0.00–0.00)

Missing light fixture

E, S

2

0.78 (0.61–0.92)

0.85 (0.00–0.92)

0.76 (0.00–0.88)

0.71 (0.00–0.90)

Exposed light bulbs

BA, BR, D, H, K, L, S

7

0.76 (0.62–0.88)

0.77 (0.64–0.88)

0.74 (0.60–0.86)

0.75 (0.62–0.88)

Shadows on stairway

E, S

2

0.76 (0.61–0.88)

0.72 (0.37–0.93)

0.85 (0.00–0.92)

0.70 (0.32–0.92)

Ambient light <300 lux

BA, BR, D, E, H, K, L, S

8

0.67 (0.46–0.87)

0.58 (0.36–0.80)

0.63 (0.41–0.82)

0.83 (0.68–0.97)

Less than two light switches

S

1

0.66 (0.24–0.92)

1.00 (0.00–0.00)

0.43 (−0.42–0.72)

0.43 (−0.42–0.72)

Switch required to turn on exterior light

E

1

0.66 (0.45–0.87)

0.87 (0.00–0.87)

0.48 (−0.03–0.87)

0.62 (0.00–0.87)

Windows without sheer coverings

BA, BR, D, H, K, L, S

7

0.53 (0.36–0.68)

0.41 (0.24–0.58)

0.65 (0.48–0.79)

0.49 (0.32–0.64)

Light switches only accessible from fully inside room

BA, BR, D, H, K, L

6

0.52 (0.32–0.70)

0.52 (0.32–0.71)

0.53 (0.31–0.71)

0.51 (0.30–0.71)

No light source in bathtub/shower with curtains closed

BA

1

0.41 (0.18–0.64)

0 .39 (−0.02–0.80)

0.51 (0.12–0.81)

0.32 (−0.08–0.71)

No nightlight/flashlight near bed or for nighttime bathroom use

BR

1

0.29 (0.09–0.50)

0.38 (0.03–0.72)

0.22 (−0.12–0.55)

0.21 (−0.11–0.52)

No light on path from bedroom to bathroom

BR

1

0.12 (−0.19–0.43)

0.33 (−0.35–0.78)

−0.28 (−0.84–0.29)

0.14 (−0.29–0.57)

Furniture

Seats without arm rests

BR, D, K, L

4

0.63 (0.48–0.78)

0.75 (0.57–0.89)

0.55 (0.33–0.78)

0.60 (0.39–0.82)

Glossy/shiny finish of countertop

K

1

0.50 (0.24–0.71)

0.48 (0.06–0.79)

0.48 (0.06–0.79)

0.54 (0.07–0.88)

Unstable furniture

BR, D, K, L

4

0.41 (0.15–0.64)

0.51 (0.22–0.76)

0.48 (0.19–0.72)

0.16 (−0.26–0.52)

Other

No handle on step stool

BR, K

2

0.67 (0.47–0.83)

0.91 (0.00–0.91)

0.51 (0.00–0.84)

0.40 (−0.20–0.85)

Inability to reach microwave with both feet on floor

K

1

0.57 (0.03–0.89)

0.65 (−0.06–0.65)

0.46 (−0.36–0.73)

0.65 (−0.06–0.65)

Step stool required to get onto bed

BR

1

0.00 (N/A)

0.00 (N/A)

0.00 (N/A)

0.00 (N/A)

Inability to reach closet items or daily kitchen items with both feet on floor

BR, K

2

−0.06 (−0.69–0.47)

−0.04 (−1.00–0.74)

−0.06 (−0.90–0.79)

−0.07 (−0.96–0.64)