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Brief Pain Inventory

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Purpose

The BPI allows patients to rate the severity of their pain and the degree to which their pain interferes with common dimensions of feeling and function.

Link to Instrument

Acronym BPI

Area of Assessment

Activities of Daily Living
Pain
Quality of Life

Assessment Type

Patient Reported Outcomes

Administration Mode

Paper & Pencil

Cost

Not Free

Cost Description

The cost of the Brief Pain Inventory is determined by the setting and intended uses of the assessment:

Clinical Practice: $100 per language, per physician using the tool, plus a processing fee

Hospital or Institution use (determined by hospital or institution size): $500 for 50 beds, $1000 for 200 beds, plus a processing fee

Funded Academic Research: $300 for the first language version, $150 for each additional language version, plus a processing fee

Non-funded Academic Research: Only a processing fee

Commercial/Pharmaceutical Research Study: $3,000 for the first language version, $1,500 for each additional language version, plus a processing fee

Reproduction in Educational Materials: Only a processing fee

Clinical Practice: No Charge

Reproduction in Educational Materials: No Charge

Non-funded Academic Research: No Charge

Funded Academic Research: $300 per project for 1st language, $150 per additional language

Commercial Research: $2,000 per project for 1st language, $1,200 per additional language

Diagnosis/Conditions

  • Cancer Rehabilitation
  • Cerebral Palsy
  • Pain Management
  • Spinal Cord Injury

Key Descriptions

  • The Brief Pain Inventory (BPI) is a self-report or interview measure that assesses the intensity of pain, impact of pain on daily function, location of pain, pain medications, and amount of pain relief in the past 24 hours or the past week.
  • There are two versions of the BPI:
    1. Short Form (BPI-SF) – 9 Items
    2. Long Form (BPI-LF) – 32 Items
  • BPI-SF assesses location of pain, pain severity, pain relief, pain interference, and additional kinds of pain.
    -- Pain intensity is measured for average pain, current pain, worst pain, and least pain, on a 0-10 numeric rating scale (NRS) with 0 = “no pain” and 10 = “worst imaginable pain”
    -- Pain relief is measured on a 0%-100% scale with 0% = “no relief” and 100% = “complete relief”
    -- Pain interference is measured for general activity, mood, walking ability, work, relationships, sleep, and enjoyment of life on a 0-10 NRS with 0 = “does not interfere” and 10 = “completely interferes”
    -- Higher scores indicated greater pain intensity or greater interference with function.
  • BPI-LF assesses socioeconomic and demographic factors, characterization of the pain, aggravating and alleviating factors, medication history and impact, in addition to the BPI-SF

Number of Items

Short: 9
Long: 32

Equipment Required

  • Brief Pain Inventory Short or Long assessment forms.

Time to Administer

10 minutes

Short Form: 5 minutes
Long Form: 10 minutes

Required Training

No Training

Age Ranges

Adult

18 - 64

years

Elderly Adult

65 +

years

Instrument Reviewers

Initially reviewed by Jessica Guzman, Elizabeth Hirsch, Evelyn Ingargiola, Occupational Therapy students at the University of Illinois at Chicago in February 2015. Updated in October 2021 by Tyler Yoshida, volunteer medical student.

Measurement Domain

Activities of Daily Living
General Health
Sensory

Osteoarthritis

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Test/Retest Reliability

Osteoarthritis : (Mendoza et al, 2006; OA of the hip: n = 467; Mean Age= 62.3; OA of the knee: n = 1019; Mean Age = 59.8)

  • Excellent: (ICC = .83 - .93)

Internal Consistency

Osteoarthritis : (Mendoza et al, 2006)

  • Excellent internal consistency for pain intensity, mood and activity scales. (Chronbach’s alphas = .86 - .96)

Construct Validity

Osteoarthritis (Mendonza et al., 2006)

Convergent validity of BPI-sf scales, the Pain Visual Analog Scale (VAS), and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)

 

BPI Pain Scale

BPI Mood Scale

BPI Activity Scale

Pain VAS

0.63

0.39

0.57

WOMAC stiffness

0.63

0.51

0.59

WOMAC physical function

0.61

0.55

0.65

Cancer

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Test/Retest Reliability

Cancer

(Saxena et. al, 1999; n = 100; Mean Age= 46; patients with cancer who spoke both English and Hindi and completed both language versions of the BPI on different days)

  • Excellent Alternate-Forms reliability for the interference and severity subscales (ICC = 0.88 and 0.95, respectively).

(Daut et al., 1983; Initial short-term, 1 day to 1 week, reliability)

  • Excellent test-rest reliability for ratings of pain “worst” (ICC = 0.93)
  • Excellent test-retest reliability for ratings of pain “usual” or “average” (ICC = 0.78)
  • Adequate test-retest reliability for ratings of pain “now” (ICC = 0.59)

Advanced Cancer Requiring Palliative Care: (Pelayo-Alvarez et al., 2013; n = 117; Mean Age = 69.4 (11.5) years; Spanish Population) 

  • Excellent test-retest reliability for the BPI Pain Intensity subscale and BPI Pain Interference subscale (Spearman correlation = 0.8 and 0.8 respectively)

Internal Consistency

Cancer (Saxena et al., 1999)

  • Excellent internal consistency for interference and severity scales of BPI-H (Cronbach's alphas =0.91 and 0.89, respectively)
  • Excellent internal consistency for interference and severity scales of English BPI (Cronbach's alphas = 0.90)

Metastatic bone pain : (Wu et. al, 2010; n = 258; median age of the study group was 67 years, with 35% (91 out of 258) and 42% (107 out of 258) having breast and genitourinary cancers, respectively)

  • Excellent internal consistency for pain, activity interference, and affect interference (Cronbach's alphas = 0.81 - 0.89)

Arabic Cancer Patients (Ballout et al., 2011; n = 75; 18 years and older, 88% older than 45 years old; over half the sample (50.7%) had metastases; patients recruited from inpatient and outpatient departments of a major tertiary care center in Beirut, Lebanon)

  • Excellent internal consistency for the Severity items (Cronbach’s alpha=0.82)
  • Excellent internal consistency for the Interference items (Cronbach’s alpha=0.92)

Criterion Validity (Predictive/Concurrent)

Concurrent Validity

Advanced Cancer Requiring Palliative Care: (Pelayo-Alvarez et al., 2013; n = 117; Mean Age = 69.4 (11.5) years; Spanish Population) 

  • Excellent concurrent validity between the BPI Pain Intensity subscale and Total Score on Palliative Outcome Scale (POS) (Spearman correlation = 0.7)
  • Excellent concurrent validity between the BPI Pain Interference subscale and Pain on POS (Spearman correlation = 0.7)
  • Adequate concurrent validity between the BPI Pain Interference subscale and Feel good on POS (Spearman correlation = 0.4)
  • Adequate concurrent validity (Spearman correlation) between BPI Pain Intensity subscale and Pain (0.5) and Physical (0.5) on Rotterdam Symptom Checklist (RSCL)
  • Adequate concurrent validity (Spearman correlation) between BPI Pain Interference subscale and Physical (0.6), Global (0.6) and Fatigue (0.6) on RSCL

Incurable Cancer: (Philip et al., 1998; n = 40)

  • Excellent concurrent validity between the BPI and the modified Edmonton Symptom Assessment System (ESAS) – Current Pain (weighted kappa = 0.61)
  • Adequate concurrent validity between the BPI and the modified ESAS – Pain Relief (weighted kappa = 0.58)

Surgical Patients with Cancer: (Tittle et al., 2003; n = 159)

  • Excellent concurrent validity (Pearson correlation) between the Visual Analog Scale (VAS) measuring pain intensity and the BPI subscales “Pain at its Worst” (0.72), “Pain right now” (0.65), and Pain Interference Subscale Total and individual items (ranging between 0.64-0.73)
  • Adequate concurrent validity between the VAS measuring pain intensity and the BPI subscale “Pain at its least” (0.58)
  • Poor concurrent validity between the VAS measuring pain intensity and the BPI subscale “Average pain” (0.01)

Construct Validity

Bone Metastases (Wu et al., 2010)

  • Discriminant
    • Tests of discriminant validity provided mixed support for Activity and Affect: the Chi-square difference test (Chi-square difference 28.4, df = 1, P < 0.001) and the confidence interval test (correlation 0.83, 95% confidence interval 0.76–0.90) were significant, but the variance extracted test failed to confirm discriminant validity because the variance extracted estimate for Affect (0.52) was lower than the square of correlation between Activity and Affect (0.69), even though the variance extracted estimate for Activity was high (0.74).

Arabic Cancer Patients (Ballout et al., 2011)

  • Excellent: Correlation of the score of the Arabic BPI item asking about pain now with the rating on the VAS was 0.68

Mixed Populations

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Test/Retest Reliability

Coronary Artery Bypass Graft (CABG) (Mendoza et al., 2004; n = 462; mean age 59.9 (8.1); time post CABG 4-14 days; 338 patients used the English versions of the assessment instruments and 124 patients were administered the German version of the assessment)

  • Excellent test-retest reliability for the Severity and Interference subscales (ICC = 0.72 and 0.95, respectively)
  • Adequate test-retest reliability for the Interference subscale on Days 4 and 5 (ICC = 0.58)

Internal Consistency

Noncancer pain (arthritis & low back pain) (Keller et al., 2004; Arthritis n = 120, LBP n = 131)

  • Excellent internal consistency for severity and interference scales(Cronbach’s alpha’s = 0.82 - 0.95)

Cardiac Surgery (Gjeilo et al., 2007; n = 534 (baseline) and n = 462 (follow-up); 1-2 days pre-surgery and 6 months post-surgery)

  • Excellent internal consistency for severity scale and interference scale at baseline (Cronbach’s alphas = 0.84 and 0.91, respectively).
  • Excellent internal consistency for severity scale and interference scale at follow-up (Cronbach’s alphas = 0.89 and 0.94, respectively)

Coronary Artery Bypass Graft (CABG) (Mendoza et al., 2004)

  • Excellent internal consistency for the Severity scale (Cronbach’s alphas = 0.85-0.91)
  • Excellent internal consistency for the Interference scale (Cronbach’s alphas = 0.90-0.92)

Criterion Validity (Predictive/Concurrent)

Cardiac Surgery (Gjeilo et al., 2007)

  • Criterion validity was assessed by Spearman’s correlation coefficients (p) between the SF-36 BP scale and the BPI scales. The correlation between the BPI pain severity index and SF- 36 BP scale was -0.47 (P<0.001) and the correlation between the BPI pain interference index and SF-36 BP scale was -0.53 (P < 0.001) at baseline. At follow-up the corresponding correlations were -0.51 (P < 0.001) and -0.64 (P < 0.001), respectively. The correlation coefficients were statistically significant and considered as moderate (between 0.47 and 0.65), which demonstrates the existence of a relationship between the scales, although without reaching redundancy.

Coronary Artery Bypass Graft (CABG) (Mendoza et al., 2004)

  • Excellent correlation (0.71-0.82) between the sternotomy pain item and the “worst pain” item
  • Excellent correlation (0.71-0.82) between the sternotomy pain item and the Pain Severity subscale
  • Adequate correlation (0.34-0.52) between the sternotomy pain item and the Pain Interference subscale

Construct Validity

Cardiac Surgery (Gjeilo et al., 2007)

  • Factor analysis at baseline, using the Kaiser criterion, detected two factors explaining a total variance of 66%. The first factor, representing interference, had an eigenvalue of 5.6 and factor 2, representing severity, had an eigenvalue of 1.7. These factor loadings correspond to the two factors—pain severity and pain interference—that the original BPI was designed to measure. A similar two-factor structure was observed at follow-up, at which the two factors explained a total variance of 75%. The first factor, interference, had an eigenvalue of 7.1 and factor 2, severity, had an eigenvalue of 1.1.

Non-cancer Pain (Arthritis & Lower Back Pain) (Keller et al., 2004)

Construct Validity of BPI as a Generic Measure of Pain: Relationship of BPI With Other Measures of Pain, Disability, and Health Status

Arthritis Patients (n = 120)

Scale

BPI Severity

BPI Interference

SF-36 BP

Chronic pain grade

   

   Intensity Scale

0.77

0.74

0.63

   Disability Scale

0.62

0.81

0.55

HAQ disability index

0.58

0.69

0.5

SF-36 health survey

 

 

 

   Bodily pain

0.74

0.7

---

   Physical functioning

0.56

0.63

0.66

   Role-physical

0.59

0.7

0.66

   General Health

0.51

0.57

0.51

   Vitality

0.4

0.51

0.52

   Social functioning

0.65

0.8

0.61

   Role-emotional

0.45

0.6

0.42

   Mental health

0.44

0.57

0.35

Low back pain patients (n = 131)

Chronic pain grade

   

   Intensity scale

0.6

0.64

0.47

   Disability scale

0.49

0.69

0.45

RDG disability index

0.57

0.81

0.53

SF-36 health survey

 

  

   Bodily pain

0.61

0.64

---

   Physical functioning

0.63

0.69

0.5

   Role-physical

0.54

0.64

0.63

   General health

0.37

0.59

0.25

   Vitality

0.47

0.7

0.55

   Social functioning

0.51

0.79

0.68

   Role-emotional

0.41

0.59

0.42

   Mental health

0.41

0.7

0.35

 

 

 

 

BPI, Brief Pain Inventory; HAQ, Health Assessment Questionnaire; RDQ, Roland Disability Questionnaire

Floor/Ceiling Effects

Cardiac Surgery (Gjeilo et al., 2007)

  • Poor: Both before and after surgery, there was a marked floor effect, 48% to 70% at baseline and 45% to 69% at six-month follow-up
  • Adequate: 0.2% to 4.5% ceiling effect at baseline and 0.1% to 2.1% at six-month follow-up

Responsiveness

Cardiac Surgery (Gjeilo et al., 2007)

  • The pain severity scale and the pain interference scale declined significantly from baseline to follow-up. These results support the responsiveness of the BPI for detecting changes. Also, the SF-36 BP scale showed a significant change from baseline to follow-up, indicating less pain after surgery.

Responsiveness of the BPI Scales and the SF-36 Bodily Pain Scale

Scale

Baseline

Follow-up

P-Value

BPI severity,

8.0 (0 - 40)

7.0 (0 - 40)

0.009c

   median (range)a,b

 

 

 

BPI interference,

15.0 (0 - 66)

6.0 (0 - 70)

0.000c

   median (range)a,d

 

 

 

SF-36 BP, mean (SD)e

45.3 (21.7)

67.7 (26.8)

0.000f

Only patients reporting pain either before or after surgery are included in the analysis.

Scale scores of the BPI scales are calculated by adding the scores of the scales’ items. Lower scores indicate less pain.

Highest possible sum is 40.

t-test

Highest possible sum is 70.

The Bodily Pain Scale of the SF-36. Higher scale scores indicate less pain.

 Wilcoxon signed-rank test.

Chronic Pain

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Cut-Off Scores

Neuropathic or Nociceptive Pain: (Erdemoglu & Koc, 2013; Turkish version and patient population; n = 224 (neuropathic pain n = 126; nociceptive pain n = 98))

  • > 20 on the BPI Pain Intensity subscale (scored from 0-40) indicates neuropathic pain (sensitivity 81.75%; specificity 50%)
  • > 44 on the BPI total scale (scored from 0-110) indicates neuropathic pain (sensitivity 79.37%; specificity = 46.94%)

 

Test/Retest Reliability

Chronic pain (Radbruch et al, 1999; n= 109; outpatients in a German pain clinic, with the retest occurring 30 to 60 minutes after the first administration)

  • Excellent test-retest reliability for pain severity, interference, and “least” pain (ICC = 0.98; ICC = 0.97; ICC = 0.78, respectively)

Neuropathic or Nociceptive Pain: (Erdemoglu & Koc, 2013; Turkish version and patient population; n = 224 (neuropathic pain n = 126; nociceptive pain n = 98)

  • Excellent test-retest reliability for BPI total score for All Pain (Pearson’s correlation coefficient = 0.97)

 

Internal Consistency

Chronic pain : (Tan, Jensen, Thornby and Shanti, 2004; n = 440 mean age = 54.9 years [range, 21-85 years] Gender: 91.8% Male Race: 72.3% white, 21.2% black, 5.4% other.)

  • Excellent internal consistency for Intensity Scale (Cronbach's alphas =.85)
  • Excellent internal consistency for Interference scale (Cronbach's alphas= .88)

Neuropathic or Nociceptive Pain: (Erdemoglu & Koc, 2013; Turkish version and patient population; n = 224 (neuropathic pain n = 126; nociceptive pain n = 98))

  • Excellent internal consistency for BPI Pain Intensity subscale for Nociceptive Pain (cronbach’s alpha = 0.83), Neuropathic Pain (0.82), and All Pain (0.84)
  • Excellent internal consistency for BPI Pain Interference subscale for Nociceptive Pain (0.83) and All Pain (0.80)
  • Adequate internal consistency for BPI Pain Interference subscale for Neuropathic Pain (0.78)

 

Criterion Validity (Predictive/Concurrent)

Chronic Pain: (Tan et al., 2004)

  • Adequate, approaching excellent correlation between the BPI interference and the Roland-Morris Disability Questionaire (RMDQ) (r = 0.57)
  • Adequate correlation between BPI intensity and the Roland-Morris Disability Questionnaire (RMDQ) (r = 0.40, t = 5.71, p < .01)
  • These scales assess related, but also distinct, dimensions. BPI Interference is measuring a concept more similar to disability than pain intensity.

Construct Validity

Chronic Pain: (Tan et al., 2004)

  • For the construct validity of the BPI in this sample of persons with chronic pain, the first factor consisted of all 7 interference items and accounted for 51.1% of the variance. The second factor consisted of the 4 pain intensity scales and accounted for another 12.5% of the variance. Both factors accounted for 63.6% of the total variance.
  • Moderate construct validity: factor analysis indicated that 11 items on the scale explained 63.6% of the variance on the construct of chronic pain

Responsiveness

Chronic Pain: (Tan et al., 2004)

  • Both BPI Intensity and Interference scales showed significant changes in the expected direction from visit 1 to visit 3, thus confirming the responsivity of this instrument for detecting improvement with pain treatment.
  • responsive in detecting change between visits; paired t-test for BPI Intensity score between visit one and two is significant at p < .01 between visit one and three significant at p < .001

 

Responsivity of BPI Scales Across Visits

Scale

Visit 1

Mean (SD)

Visit 2

Mean (SD)

Visit 3

Mean (SD)

T Value*

BPI Intensity

7.07 (1.60)

Visit 1

 

Visit 1

6.63 (1.81)

Visit 2

Visit 2

 

6.14 (2.03)

 

Visit 3

Visit 3

 

2.52*

2.83*

5.33**

BPI Interference

7.42 (1.98)

Visit 1

 

Visit 1

6.71 (2.46)

Visit 2

Visit 2

 

6.46(2.48)

 

Visit 3

Visit 3

 

3.56**

1.12

4.66**

*Paired t-test used

*p<.01

**p<.001

N= 440, 189, and 97, for visits 1,2, and 3. The avg number of days between visits was 27.73.

Emergency Room Patients/Hospitalized Patients

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Normative Data

Patients presenting to the emergency department (ED) with chest, abdominal, or musculoskeletal pain: (Im et al., 2020; n = 100; mean age = 37.9)

  • Median Pain Severity score: 21 (on 0-40 scale)
    • 1st to 3rd quartile range: 15-28
  • Median Pain Interference score: 36 (on 0-70 scale)
    • 1st to 3rd quartile range: 24-50
  • Median total BPI-SF score: 57 (on 0-110 scale)
    • 1st to 3rd quartile range: 43-73

Internal Consistency

Patients presenting to the ED with chest, abdominal, or musculoskeletal pain: (Im et al., 2020; n = 100; mean age = 37.9)

  • Excellent internal consistency for the BPI Pain Intensity subscale (cronbach’s ? = 0.86) and the Pain Interference subscale (0.86) 
  • Excellent internal consistency for the following BPI Pain Intensity individual items: “Pain at its worst” (0.87), “Pain on average” (0.82), and “Pain right now” (0.80)
  • Excellent internal consistency for each Pain Interference individual item (ranging from 0.82-0.86)
  • Adequate internal consistency for the BPI Pain Intensity “pain at its least” item (0.79)

Pulmonary Diseases

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Test/Retest Reliability

COPD: (Chen et al., 2018; n = 132; Mean Age = 71)

  • Excellent test-retest reliability for the total BPI (ICC = 0.93)
  • Excellent test-retest reliability for the BPI Pain Intensity subscale (ICC = 0.76) and the individual items “Pain at its least” (0.81) and “Pain on average” (0.75)
  • Excellent test-retest reliability for the BPI Pain Interference subscale (ICC = 0.91) and for the following individual items: Mood (0.85), Normal work (0.83), Relations (0.82), Sleep (0.82), and Enjoyment of life (0.83)
  • Adequate test-retest reliability for the BPI Pain Intensity individual items “Pain at its worst” (0.72) and “Pain right now” (0.67)
  • Adequate test-retest reliability for the BPI Pain Interference individual items General activity (0.74) and Walking ability (0.73)

Internal Consistency

COPD: (Chen et al., 2018; n = 132; Mean Age = 71)

  • Excellent internal consistency for the BPI Pain Intensity subscale (cronbach’s ? = 0.91) and for each Pain Intensity individual item (ranging from 0.86-0.91) 
  • Excellent internal consistency for the BPI Pain Interference subscale (cronbach’s ? = 0.94) and for each Pain Interference individual item (ranging from 0.92-0.93) 

Construct Validity

Convergent validity:

COPD: (Chen et al., 2018; n = 132; Mean Age = 71)

  • Excellent convergent validity between the BPI total score and the Short-Form McGill Pain Questionnaire (SF-MPQ) (Spearman correlation coefficient = 0.79)
  • Excellent convergent validity between the BPI Pain Intensity subscale and the SF-MPQ Sensory subscale (0.72)
  • Excellent convergent validity between the SF-MPQ VAS and the BPI total score (0.88), Pain Intensity subscale (0.86), and Pain Interference subscale (0.82)

Discriminant validity:

COPD: (Chen et al., 2018; n = 132; Mean Age = 71)

  • Adequate discriminant validity between BPI total score and the 36-Item Short Form Survey (SF-36) Bodily pain domain (-0.54)
  • Poor discriminant validity between BPI total score and the SF-36 domains Physical functioning (Spearman correlation coefficient = -0.29), Role-physical (-0.22), General health perceptions (-0.31), Vitality (-0.23), Social functioning (-0.22), Role-emotional (-0.22), and General mental health (-0.22)

Back Pain

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Construct Validity

Construct Validity: 

Construct validity was measured using confirmatory factor analysis to partially confirm the two-factor structure of the BPI because the goodness of fit was acceptable at 0.91. However, the normed fit index and adjusted goodness of fit index were slightly below the 0.90 threshold, at 0.89 and 0.87 respectively, and the standardized root mean square residual was 0.38, higher than the 0.08 threshold. 

Convergent Validity:

Low Back Pain: (Song et al., 2016; Chinese version; n = 271; Mean Age = 57.1 years)

  • Adequate convergent validity between the BPI Pain Interference subscale and the Owestry Disability Index (ODI) score (Spearman’s correlation = 0.66)
  • Adequate convergent validity between the BPI Pain Intensity subscale and the ODI score (0.39) 

Chronic Low Back Pain: (Shafshak & Elnemr, 2021; n = 100; Mean Age = 51.9 years)

  • Excellent convergent validity between the BPI Pain Severity subscale and the Visual Analogue Scale (VAS) (Spearman’s correlation = 0.97) and the Numeric Rating Scale (NRS) (0.95)
  • Excellent convergent validity between the BPI Pain Interference subscale and the VAS (0.95) and the NRS (0.92)

 

Bibliography

Ballout, S., Noureddine, S., Huijer, H. A. S., & Kanazi, G. (2011). Psychometric evaluation of the Arabic Brief Pain Inventory in a sample of Lebanese cancer patients. Journal of pain and symptom management, 42(1), 147-154.

Chen, Y.W., HajGhanbari, B., Road, J.D., Coxson, H.O., Camp P.G., & Reid, W.D. (2018). Reliability and validity of the Brief Pain Inventory in individuals with chronic obstructive pulmonary disease. Eur J Pain 22: 1718-1726.

Daut, R.L., Cleeland, C.S., Flanery, R.C. (1983) Development of the Wisconsin Brief Pain Questionnaire to assess pain in cancer and other diseases. Pain 17(2): 197- 210.

Erdemoglu, A.K., Koc, R. (2013). Brief Pain Inventory score identifying and discriminating neuropathic and nociceptive pain. Acta Neurol Scand 128: 351-358.

Gjeilo, K.H., Stenseth, R., Wahba, A., Lydersen, S., Klepstad, P. (2007) Validation of the Brief Pain Inventory Patients Six Months After Cardiac Surgery. Journal of Pain and Symptom Management, 34(6), 648-656.

Im, D.D., Jambaulidar, G.D., Kikut, A., Gale, J., & Weiner, S.G. (2020). Brief Pain Inventory -- Short form: A new method for assessing pain in the emergency department. Pain Med 21(12): 3263-3269.

Keller, S., Bann, C.M., Dodd, S.L., Schein, J., Mendoza, T.R., Cleeland, C.S. (2004) Validity of the Brief Pain Inventory for Use in Documenting the Outcomes of Patients With Noncancer Pain. Clinical Journal of Pain, 20(5), 309-318.

Mendoza, T. R., Chen, C., Brugger, A., Hubbard, R., Snabes, M., Palmer, S. N., ... & Cleeland, C. S. (2004). The utility and validity of the modified brief pain inventory in a multiple-dose postoperative analgesic trial. The Clinical journal of pain, 20(5), 357-362.

Mendoza, T., Mayne, T., Rublee, D., Cleeland, C. (2006). Reliability and validity of a modified Brief Pain Inventory short form in patients with osteoarthritis. European Journal of Pain, 10 (2006). 353-361. http://doi:10.1016/j.ejpain.2005.06.002

Pelayo-Alvarez, M., Perez-Hoyos, S., & Agra-Varela, Y. (2013). Reliability and Concurrent Validity of the Palliative Outcome Scale, Rotterdam Symptom Checklist, and the Brief Pain Inventory. J Palliat Med 16(8): 867-874.

Philip, J., Smith, W.B., Craft, P., & Lickiss, N. (1998). Concurrent validity of the modified Edmonton Symptom Assessment System with the Rotterdam Symptom Checklist and the Brief Pain Inventory. Support Care Cancer 6: 539-541.

Radbruch, L., Loick, G., Kiencke, P., Lindena, G., Sabatowski, R., Grond, S., Lehmann, K. A., Cleeland, C.S. (1999) Validation of the German version of the Brief Pain Inventory. Journal of Pain and Symptom Management,18(3), 180-187.

Saxena, A., Mendoza, T., Cleeland, C.S. (1999) The assessment of cancer pain in north India: the validation of the Hindi Brief Pain Inventory -- BPI-H. Journal of Pain and Symptom Management, 17(1), 27-41.

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