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Table 4 Criterion validity summary statistics for senior clinician (Sensitivity, specificity and positive predictive value) & inter-rater reliability between expert and senior clinicians (Kappa and strength of agreement)

From: The Queensland high risk foot form (QHRFF) – is it a reliable and valid clinical research tool for foot disease?

QHRFF field

%

K(SE)

Strength of agreement [[37]]

Sensitivity (95% CI)

Specificity (95% CI)

PPV (95% CI)

General demographics

      

Any indigenous status

100

--

--

--

1.00 (0.90-1.00)

--

Health professionals attending (in the past week)

   

Podiatrist

100

--

--

1.00 (0.90-1.00)

--

1.00 (0.90-1.00)

GP

86.0

0.64 (0.14)

Substantial

0.80 (0.44-0.96)

0.88 (0.71-0.96)

0.67 (0.35-0.88)

Nurse

93.0

0.83 (0.09)

Near perfect

0.92 (0.60-1.00)

0.94 (0.77-0.99)

0.85 (0.54-0.97)

Orthotist

100

--

--

--

1.00 (0.90-1.00)

--

Physician

93.0

--

--

0 (0 – 0.95)

0.95 (0.83-0.99)

0 (0 – 0.80)

Surgeon

95.3

0.64 (0.24)

Substantial

0.67 (0.13-0.98)

0.98 (0.85-1.00)

0.67 (0.13-0.98)

Other

100

--

--

--

1.00 (0.90-1.00)

--

Medical co-morbidity history

    

Any medical (diabetes) history

100

1.00 (0.01)

Near perfect

1.00 (0.88-1.00)

1.00 (0.60-1.00)

1.00 (0.88-1.00)

Diabetes duration#

 

0.90 (0.80– 0.95)

Strong

   

Recent BGLs > 15 mmol/L

93.0

0.69 (0.16)

Substantial

0.57 (0.20-0.88)

1.00 (0.88-1.00)

1.00 (0.40-1.00)

HbA1c result#

 

1.00 (0.99–1.00)

Strong

   

Hypertension

93.0

0.83 (0.09)

Near perfect

0.97 (0.81-1.00)

0.85 (0.54-0.97)

0.94 (0.77-0.99)

Dyslipidaemia

95.3

0.90 (0.07)

Near perfect

0.96 (0.78-1.00)

0.94 (0.71-1.00)

0.96 (0.78-1.00)

Smoker

90.7

0.72 (0.13)

Substantial

0.64 (0.32-0.88)

1.00 (0.87-1.00)

1.00 (0.56-1.00)

CVD

90.7

0.81 (0.09)

Near perfect

0.86 (0.63-0.96)

0.95 (0.75-1.00)

0.95 (0.72-1.00)

CKD

81.4

0.49 (0.15)

Moderate

0.46 (0.20-0.74)

0.97 (0.81-1.00)

0.86 (0.42-0.99)

ESRF

1.00

1.00 (0.01)

Near perfect

1.00 (0.05-1.00)

1.00 (0.90-1.00)

1.00 (0.05-1.00)

Other (non-listed)

57.1

0.09 (0.12)

Slight

0.57 (0.40-0.73)

0.57 (0.20-0.88)

0.87 (0.65-0.97)

High-risk history

    

Neuropathy

93.0

0.73 (0.15)

Substantial

0.95 (0.80-0.99)

0.83 (0.36-0.99)

0.97 (0.84-1.00)

PAD

88.4

0.77 (0.10)

Substantial

0.86 (0.63-0.96)

0.91 (0.69-0.98)

0.90 (0.67-0.98)

Previous foot ulcer

79.1

0.28 (0.18)

Fair

0.84 (0.67-0.93)

0.50 (0.14-0.86)

0.91 (0.75-0.98)

Current foot ulcer

95.3

--

--

0.98 (0.86-1.00)

0 (0 – 0.95)

0.98 (0.86-1.00)

New foot ulcer

93.0

--

--

0.95 (0.82-0.99)

0 (0 – 0.95)

0.98 (0.86-1.00)

Previous amputation

97.7

0.95 (0.05)

Near perfect

0.94 (0.69-1.00)

1.00 (0.84-1.00)

1.00 (0.76-1.00)

Clinical diagnoses of high-risk factors

   

Neuropathy

97.7

0.90 (0.10)

Near perfect

0.97 (0.85-1.00)

1.00 (0.46-1.00)

1.00 (0.88-1.00)

Any PAD

93.0

0.86 (0.8)

Near perfect

0.91 (0.69-0.98)

0.95 (0.74-1.00)

0.95 (0.74-1.00)

Acute Charcot

100

1.00 (0.01)

Near perfect

1.00 (0.05-1.00)

1.00 (0.90-1.00)

1.00 (0.05-1.00)

Foot deformity

86.0

0.51 (0.16)

Moderate

1.00 (0.87-1.00)

0.4 (0.14-0.73)

0.85 (0.69-0.94)

Acute risk classification

97.7

--

--

1.00 (0.90-1.00)

0 (0 – 0.95)

0.98 (0.86-1.00)

Clinical diagnoses of foot disease

    

Ulcer type: neuropathic (neuropathic or neuroisch.)

90.7

0.76 (0.11)

Substantial

0.88 (0.72-0.96)

1.0 (0.63-1.00)

1.00 (0.86-1.00)

Ulcer type: ischaemic

79.1

0.58 (0.13)

Moderate

0.75 (0.51-0.90)

0.83 (0.60-0.94)

0.79 (0.54-0.93)

(Neuroisch. or ischaemic)

Combined surface area mm2#

 

0.93 (0.87–0.96)

Strong

   

Any clinical infection

88.4

0.72 (0.12)

Substantial

0.71 (0.42-0.90)

0.97 (0.80-1.00)

0.91 (0.57-1.00)

UTWCS (Grade 1A)

83.7

0.65 (12)

Substantial

0.85 (0.56-0.97)

0.83 (0.64-0.93)

0.71 (0.44-0.89)

Deep ulcer

95.3

0.81 (0.13)

Near perfect

0.71 (0.30-0.95)

0.97 (0.84-1.00)

0.83 (0.36-0.99)

(Grade 2 or 3)^

Clinical management principles performed

   

Ulcer debridement is required

95.3

0.66 (0.01)

Substantial

1.00 (0.89-1.00)

1.00 (0.20-1.00)

1.00 (0.89-1.00)

Dressing is optimum

100

--

--

1.00 (0.90-1.00)

--

1.00 (0.90-1.00)

Antibiotics are required

93.0

0.82 (0.10)

Near perfect

0.83 (0.51-0.97)

0.94 (0.77-0.99)

0.83 (0.51-0.97)

Off-loading is optimum

93.0

0.80 (0.11)

Substantial

0.80 (0.44-0.96)

0.97 (0.82-1.00)

0.89 (0.51-0.99)

Footwear is optimum

72.1

0.31 (0.16)

Fair

0.50 (0.20-0.80)

0.82 (0.64-0.92)

0.45 (0.18-0.75)

Educated patient

97.7

--

--

0.98 (0.86-1.00)

--

1.00 (0.90-1.00)

  1. K = Kappa; (SE) = Standard Error; % = Percentage agreement; PPV = Positive Predictive Value.
  2. -- = Measure of agreement was unable to be calculated because at least one variable was a constant.
  3. GP = General Practitioner; CVD = Cardiovascular Disease; ESRF = End Stage Renal Failure; PAD = Peripheral Arterial Disease; UTWCS = University of Texas Wound Classification System.
  4. # = Intraclass correlation (ICC) (Standard Deviation (SD)) for continuous data.
  5. ^ = Depth was determined from the UTWCS score.