Pain self-efficacy beliefs and pain behaviour. A prospective study
Abstract
This study examined the relationship between pain self-efficacy beliefs and a range of pain behaviours, as measured by the pain behaviour questionnaire (PBQ), using a prospective design. A heterogeneous sample of 145 chronic pain patients completed sets of questionnaires on four occasions over a nine-month period. Multiple hierarchical regression analyses revealed that the subjects' confidence in their ability to perform a range of tasks despite pain (assessed at baseline), was predictive of total pain behaviour and avoidance behaviour over the nine-month study period. This finding was particularly significant because the analyses controlled for the possible effects of pain severity (at each measurement occasion), pain chronicity, age, gender, physical disability, depression, neuroticism and catastrophising. These findings suggest that pain self-efficacy beliefs are an important determinant of pain behaviours and disability associated with pain, over and above the effects of pain, distress and personality variables. In particular, higher pain self-efficacy beliefs are predictive of reduced avoidance behaviours over an extended period.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
The modified RMDQ has demonstrated excellent internal reliability (Cronbach of 0.92), test-retest reliability and validity in participants with persistent pain in a diverse group of health conditions and body sites.
“The modified RMDQ has demonstrated excellent internal reliability (Cronbach of 0.92),43 test–retest reliability and validity in participants with persistent pain in a diverse group of health conditions and body sites.44”
Cites
Tabachnick, B. G., & Fidell, L. S. (1983) · Cited by 79,888 · see citing works
Self-efficacy: Toward a unifying theory of behavioral change
Bandura, A. (1977) · Psychological Review · doi:10.1037/0033-295x.84.2.191 · Cited by 43,925 · see citing works
Cognitive Therapy for Depression
(2012) · PsycEXTRA Dataset · doi:10.1037/e675542012-001 · Cited by 9,678 · see citing works
Fear-avoidance and its consequences in chronic musculoskeletal pain: a state of the art.
Vlaeyen, J. W. S., & Linton, S. J. (2000) · Pain · doi:10.1016/s0304-3959(99)00242-0 · Cited by 4,931 · see citing works
The Sickness Impact Profile: Development and Final Revision of a Health Status Measure
Bergner, M., Bobbitt, R. A., Carter, W. B., & Gilson, B. S. (1981) · Medical Care · doi:10.1097/00005650-198108000-00001 · Cited by 4,619 · see citing works
A Study of the Natural History of Back Pain: Part I
ROLAND, M., & MORRIS, R. (1983) · Spine · doi:10.1097/00007632-198303000-00004 · Cited by 3,395 · cited 5× · see citing works
“A precedent for this can be seen in Jensen et al. (1992), p. 157 when they used the same items (less the constancy one) that Roland and Morris (1983) had extracted from the SIP, but left in the original attribution to ‘health’ rather than ‘back’ with their heterogeneous pain patient sample.”
InfluentialRosenstiel, A. K., & Keefe, F. J. (1983) · Pain · doi:10.1016/0304-3959(83)90125-2 · Cited by 2,314 · see citing works
Revised NEO Personality Inventory (NEO PI-R) and NEO Five-Factor Inventory (NEO-FFI)
Costa, P. T., & McCrea, R. B. (1992) · Medical Entomology and Zoology · Cited by 1,758 · see citing works
Behavioral methods for chronic pain and illness
Fordyce, W. E. (1977) · Pain · doi:10.1016/0304-3959(77)90029-x · Cited by 1,630 · see citing works
Morley, S., Eccleston, C., & Williams, A. (1999) · Pain · doi:10.1016/s0304-3959(98)00255-3 · Cited by 1,597 · see citing works
Development and evaluation of a scale to measure perceived self‐efficacy in people with arthritis
Lorig, K., Chastain, R. L., Ung, E., Shoor, S., & Holman, H. R. (1989) · Arthritis & Rheumatism · doi:10.1002/anr.1780320107 · Cited by 1,590 · see citing works
Williams, A. C. D. C. (1995) · Journal of Psychosomatic Research · doi:10.1016/0022-3999(95)90016-0 · Cited by 1,475 · see citing works
Keefe, F. J., Lefebvre, J. C., Egert, J. R., Affleck, G., Sullivan, M. J., & Caldwell, D. S. (2000) · Pain · doi:10.1016/s0304-3959(00)00296-7 · Cited by 735 · see citing works
Coping with rheumatoid arthritis pain: catastrophizing as a maladaptive strategy
Keefe, F. J., Brown, G. K., Wallston, K. A., & Caldwell, D. S. (1989) · Pain · doi:10.1016/0304-3959(89)90152-8 · Cited by 694 · see citing works
Turner, J. A., Jensen, M. P., & Romano, J. M. (2000) · Pain · doi:10.1016/s0304-3959(99)00259-6 · Cited by 487 · see citing works
Vlaeyen, J. W. S., de Jong, J., Geilen, M., Heuts, P. H. T. G., & van Breukelen, G. (2001) · Behaviour Research and Therapy · doi:10.1016/s0005-7967(99)00174-6 · Cited by 469 · see citing works
Asmundson, G. J. G., Norton, P. J., & Norton, G. R. (1999) · Clinical Psychology Review · doi:10.1016/s0272-7358(98)00034-8 · Cited by 461 · see citing works
Development of an observation method for assessing pain behavior in chronic low back pain patients
Keefe, F. J., & Block, A. R. (1982) · Behavior Therapy · doi:10.1016/s0005-7894(82)80001-4 · Cited by 451 · see citing works
Biopsychosocial perspective on chronic pain.
Turk, D. C., & Monarch, E. S. (1996) · Cited by 439 · see citing works
Arnstein, P., Caudill, M., Mandle, C. L., Norris, A., & Beasley, R. (1999) · Pain · doi:10.1016/s0304-3959(98)00220-6 · Cited by 436 · see citing works
Avoidance behaviour and its role in sustaining chronic pain
Philips, H. C. (1987) · Behaviour Research and Therapy · doi:10.1016/0005-7967(87)90005-2 · Cited by 434 · see citing works
Relationship of pain-specific beliefs to chronic pain adjustment
Jensen, M. P., Turner, J. A., Romano, J. M., & Lawler, B. K. (1994) · Pain · doi:10.1016/0304-3959(94)90005-1 · Cited by 361 · see citing works
An empirical assessment of pain beliefs
Williams, D. A., & Thorn, B. E. (1989) · Pain · doi:10.1016/0304-3959(89)90095-x · Cited by 328 · see citing works
Control beliefs, coping efforts, and adjustment to chronic pain.
Jensen, M. P., & Karoly, P. (1991) · Journal of Consulting and Clinical Psychology · doi:10.1037//0022-006x.59.3.431 · Cited by 312 · see citing works
Control beliefs, coping efforts, and adjustment to chronic pain
Jensen, M. P., & Karoly, P. (1991) · Journal of Consulting and Clinical Psychology · doi:10.1037/0022-006x.59.3.431 · Cited by 312 · see citing works
Psychological Approaches to Pain Management
Befner, B. A. (1997) · Journal of Psychosocial Nursing and Mental Health Services · doi:10.3928/0279-3695-19971201-23 · Cited by 299 · see citing works
Jensen, M. P., Turner, J. A., & Romano, J. M. (1991) · Pain · doi:10.1016/0304-3959(91)90095-f · Cited by 282 · see citing works
Nicholas, M. K., Wilson, P. H., & Goyen, J. (1992) · Pain · doi:10.1016/0304-3959(92)90082-m · Cited by 271 · see citing works
Self-citationDeyo, R. A. (1986) · Spine · doi:10.1097/00007632-198611000-00017 · Cited by 238 · see citing works
Coping strategies predict disability in patients with primary fibromyalgia
Martin, M. Y., Bradley, L. A., Alexander, R. W., Alarcón, G. S., Triana-Alexander, M., Aaron, L. A., & Alberts, K. R. (1996) · Pain · doi:10.1016/s0304-3959(96)03179-x · Cited by 228 · see citing works
Role of self-efficacy in rehabilitation outcome among chronic low back pain patients.
Altmaier, E. M., Russell, D. W., Kao, C. F., Lehmann, T. R., & al, E. (1993) · Journal of Counseling Psychology · doi:10.1037/0022-0167.40.3.335 · Cited by 228 · see citing works
Inpatient vs. outpatient pain management: results of a randomised controlled trial
de Williams, C. A. C., Richardson, P. H., Nicholas, M. K., Pither, C. E., Harding, V. R., Ridout, K. L., Ralphs, J. A., Richardson, I. H., Justins, D. M., & Chamberlain, J. H. (1996) · Pain · doi:10.1016/0304-3959(96)02996-x · Cited by 199 · see citing works
Inpatient vs outpatient pain management: Results of a randomised controlled trial
(1996) · Pain · Cited by 199 · see citing works
Jensen, M. P., Strom, S. E., Turner, J. A., & Romano, J. M. (1992) · Pain · doi:10.1016/0304-3959(92)90156-6 · Cited by 187 · see citing works
Lackner, J. M., Carosella, A. M., & Feuerstein, M. A. (1996) · Journal of Consulting and Clinical Psychology · doi:10.1037//0022-006x.64.1.212 · Cited by 186 · see citing works
The behavioral management of chronic pain: A response to critics
Fordyce, W. E., Roberts, A. H., & Sternbach, R. A. (1985) · Pain · doi:10.1016/0304-3959(85)90172-1 · Cited by 176 · see citing works
Analyzing chronic low back pain: the relative contribution of pain coping strategies
Keefe, F. J., Crisson, J. E., Urban, B. J., & Williams, D. A. (1990) · Pain · doi:10.1016/0304-3959(90)91126-4 · Cited by 165 · see citing works
Osteoarthritic knee pain: a behavioral analysis
Keefe, F. J., Caldwell, D. S., Queen, K. T., Gil, K. M., Martinez, S., Crisson, J. E., Ogden, W., & Nunley, J. (1987) · Pain · doi:10.1016/0304-3959(87)90066-2 · Cited by 164 · see citing works
Lackner, J. M., Carosella, A. M., & Feuerstein, M. (1996) · Journal of Consulting and Clinical Psychology · doi:10.1037/0022-006x.64.1.212 · Cited by 153 · see citing works
Dolce, J. J., Crocker, M. F., Moletteire, C., & Doleys, D. M. (1986) · Pain · doi:10.1016/0304-3959(86)90122-3 · Cited by 150 · see citing works
Main, C. J., & Waddell, G. (1991) · Pain · doi:10.1016/0304-3959(91)90112-b · Cited by 148 · see citing works
Pain > pain behaviors: The utility and limitations of the pain behavior construct
Turk, D. C., & Flor, H. (1987) · Pain · doi:10.1016/0304-3959(87)90158-8 · Cited by 140 · see citing works
Watson, P. J., Booker, C. K., & Main, C. J. (1997) · Journal of Musculoskeletal Pain · doi:10.1300/j094v05n04_05 · Cited by 137 · see citing works
Wade, J. B., Dougherty, L. M., Hart, R. P., Rafii, A., & Price, D. D. (1992) · Pain · doi:10.1016/0304-3959(92)90010-9 · Cited by 136 · see citing works
Self-efficacy and pain behavior among subjects with fibromyalgia
Buckelew, S. P., Parker, J. C., Keefe, F. J., Deuser, W. E., Crews, T. M., Conway, R., Kay, D. R., & Hewett, J. E. (1994) · Pain · doi:10.1016/0304-3959(94)90024-8 · Cited by 136 · see citing works
Pain beliefs: assessment and utility
Williams, D. A., Robinson, M. E., & Geisser, M. E. (1994) · Pain · doi:10.1016/0304-3959(94)90049-3 · Cited by 125 · see citing works
Keefe, F. J., Caldwell, D. S., Martinez, S., Nunley, J., Beckham, J. C., & Williams, D. A. (1991) · Pain · doi:10.1016/0304-3959(91)90070-e · Cited by 117 · see citing works
Pain coping strategies in a Dutch population of chronic low back pain patients
Spinhoven, P., ter Kuile, M. M., Linssen, C. G. A., & Gazendam, B. (1989) · Pain · doi:10.1016/0304-3959(89)90155-3 · Cited by 113 · see citing works
Direct observation of pain behavior in low back pain patients during physical examination
Keefe, F. J., Wilkins, R. H., & Cook, W. A. (1984) · Pain · doi:10.1016/0304-3959(84)90811-x · Cited by 107 · see citing works
The effects of behavioural treatment on chronic pain
Philips, H. C. (1987) · Behaviour Research and Therapy · doi:10.1016/0005-7967(87)90014-3 · Cited by 93 · see citing works
The components of pain behaviour report
Philips, H. C., & Jahanshahi, M. (1986) · Behaviour Research and Therapy · doi:10.1016/0005-7967(86)90082-3 · Cited by 75 · see citing works
An evaluation of a behavioral program for chronic pain
Cinciripini, P. M., & Floreen, A. C. (1982) · Journal of Behavioral Medicine · doi:10.1007/bf00846164 · Cited by 74 · see citing works
Anderson, K. O., Keefe, F. J., Bradley, L. A., McDaniel, L. K., Young, L. D., Turner, R. A., Agudelo, C. A., Semble, E. L., & Pisko, E. J. (1988) · Pain · doi:10.1016/0304-3959(88)90199-6 · Cited by 72 · see citing works
Gibson, E., & Strong, J. (1996) · Journal of Occupational Rehabilitation · doi:10.1007/bf02110753 · Cited by 71 · see citing works
(1991) · PubMed · Cited by 65 · see citing works
Williams, A. C. D. C., Nicholas, M. K., Richardson, P. H., Pither, C. E., & Fernandes, J. (1999) · Pain · doi:10.1016/s0304-3959(99)00074-3 · Cited by 63 · see citing works
Self-citationAttrition from a pain management programme
Coughlan, G., Ridout, K., Williams, A. C. D. C., & Richardson, P. H. (1995) · British Journal of Clinical Psychology · doi:10.1111/j.2044-8260.1995.tb01481.x · Cited by 48 · see citing works
The pain beliefs and perceptions inventory: a British replication
Morley, S., & Wilkinson, L. (1995) · Pain · doi:10.1016/0304-3959(94)00202-p · Cited by 45 · see citing works
Pain behavior predictors among fibromyalgia patients
Baumstark, K. E., Buckelew, S. P., Sher, K. J., Beck, N. C., Buescher, K. L., Hewett, J. E., & Crews, T. M. (1993) · Pain · doi:10.1016/0304-3959(93)90009-e · Cited by 23 · see citing works
Behavioral management of chronic pain
Slater, M. A., & Good, A. B. (1991) · Holistic Nursing Practice · doi:10.1097/00004650-199110000-00012 · Cited by 17 · see citing works
Flagged first, then by citations
Cited by
Sorted by citations
The biopsychosocial approach to chronic pain: Scientific advances and future directions.
Gatchel, R. J., Peng, Y. B., Peters, M. L., Fuchs, P. N., & Turk, D. C. (2007) · Psychological Bulletin · doi:10.1037/0033-2909.133.4.581 · Cited by 3,392 · see citing works
The pain self-efficacy questionnaire: Taking pain into account
Nicholas, M. K. (2007) · European Journal of Pain · doi:10.1016/j.ejpain.2005.12.008 · Cited by 1,656 · see citing works
Self-citationMarks, R., Allegrante, J. P., & Lorig, K. (2005) · Health Promotion Practice · doi:10.1177/1524839904266790 · Cited by 738 · see citing works
Outcome measures in chronic low back pain
Maughan, E. F., & Lewis, J. S. (2010) · European Spine Journal · doi:10.1007/s00586-010-1353-6 · Cited by 438 · see citing works
Koumantakis, G. A., Watson, P. J., & Oldham, J. A. (2005) · Physical Therapy · doi:10.1093/ptj/85.3.209 · Cited by 433 · see citing works
Denison, E., Åsenlöf, P., & Lindberg, P. (2004) · Pain · doi:10.1016/j.pain.2004.07.001 · Cited by 392 · see citing works
How important are back pain beliefs and expectations for satisfactory recovery from back pain?
Main, C. J., Foster, N., & Buchbinder, R. (2010) · Best Practice & Research Clinical Rheumatology · doi:10.1016/j.berh.2009.12.012 · Cited by 271 · see citing works
Nicholas, M. K., McGuire, B. E., & Asghari, A. (2015) · The Journal of Pain · doi:10.1016/j.jpain.2014.11.002 · Cited by 241 · see citing works
Self-citationMorley, S., Williams, A., & Hussain, S. (2008) · Pain · doi:10.1016/j.pain.2008.02.025 · Cited by 194 · see citing works
Psychological factors and treatment opportunities in low back pain
Pincus, T., & McCracken, L. M. (2013) · Best Practice & Research Clinical Rheumatology · doi:10.1016/j.berh.2013.09.010 · Cited by 144 · see citing works
Self-management intervention for chronic pain in older adults: A randomised controlled trial
Nicholas, M. K., Asghari, A., Blyth, F. M., Wood, B. M., Murray, R., McCabe, R., Brnabic, A., Beeston, L., Corbett, M., Sherrington, C., et al. (2013) · Pain · doi:10.1016/j.pain.2013.02.009 · Cited by 137 · see citing works
Self-citationSharpe, L., Ianiello, M., Dear, B. F., Perry, K. N., Refshauge, K., & Nicholas, M. K. (2012) · Pain · doi:10.1016/j.pain.2011.12.014 · Cited by 136 · see citing works
Self-citationA meta-analysis of fear-avoidance and pain intensity: the paradox of chronic pain
Kroska, E. B. (2016) · Scandinavian Journal of Pain · doi:10.1016/j.sjpain.2016.06.011 · Cited by 128 · see citing works
Multi-disciplinary interventions for chronic pain involving education: a systematic review
Joypaul, S., Kelly, F., McMillan, S. S., & King, M. A. (2019) · PLOS ONE · doi:10.1371/journal.pone.0223306 · Cited by 119 · see citing works
Investigating acceptance in adjustment to chronic pain: Is acceptance broader than we thought?
Nicholas, M. K., & Asghari, A. (2006) · Pain · doi:10.1016/j.pain.2006.04.032 · Cited by 100 · see citing works
Self-citationZadro, J. R., Shirley, D., Simic, M., Mousavi, S. J., Ceprnja, D., Maka, K., Sung, J., & Ferreira, P. (2019) · Physical Therapy · doi:10.1093/ptj/pzy112 · Cited by 94 · see citing works
Chronic pain couples: perceived marital interactions and pain behaviours
Newton-John, T. R., & de C Williams, A. C. (2006) · Pain · doi:10.1016/j.pain.2006.02.009 · Cited by 92 · see citing works
The Positive Consequences of Pain: A Biopsychosocial Approach
Bastian, B., Jetten, J., Hornsey, M. J., & Leknes, S. (2014) · Personality and Social Psychology Review · doi:10.1177/1088868314527831 · Cited by 91 · see citing works
Chisari, C., Monajemi, M. B., Scott, W., Moss‐Morris, R., & McCracken, L. M. (2021) · European Journal of Pain · doi:10.1002/ejp.1668 · Cited by 83 · see citing works
Perry, K. N., Nicholas, M. K., & Middleton, J. W. (2010) · The Clinical Journal of Pain · doi:10.1097/ajp.0b013e3181bff8f3 · Cited by 80 · see citing works
Self-citationChiarotto, A., Vanti, C., Ostelo, R. W., Ferrari, S., Tedesco, G., Rocca, B., Pillastrini, P., & Monticone, M. (2015) · Pain Practice · doi:10.1111/papr.12242 · Cited by 73 · see citing works
Mangels, M., Schwarz, S., Worringen, U., Holme, M., & Rief, W. (2009) · The Clinical Journal of Pain · doi:10.1097/ajp.0b013e3181925791 · Cited by 74 · see citing works
The role of psychological factors in the fatigue of primary biliary cirrhosis
Blackburn, P., Freeston, M., Baker, C. R., Jones, D. E. J., & Newton, J. L. (2007) · Liver International · doi:10.1111/j.1478-3231.2007.01500.x · Cited by 67 · see citing works
Acceptance as a process variable in relation to catastrophizing in multidisciplinary pain treatment.
Baranoff, J., Hanrahan, S. J., Kapur, D., & Connor, J. P. (2013) · European Journal of Pain · doi:10.1002/j.1532-2149.2012.00165.x · Cited by 61 · see citing works
Firth, A. M., Cavallini, I., Sütterlin, S., & Lugo, R. G. (2019) · Psychology Research and Behavior Management · doi:10.2147/prbm.s206666 · Cited by 57 · see citing works
Validation of the chronic pain acceptance questionnaire-8 in an Australian pain clinic sample
Baranoff, J., Hanrahan, S. J., Kapur, D., & Connor, J. P. (2014) · International Journal of Behavioral Medicine · doi:10.1007/s12529-012-9278-6 · Cited by 46 · see citing works
Group membership and staff turnover affect outcomes in group CBT for persistent pain
de C. Williams, A. C., & Potts, H. W. W. (2010) · Pain · doi:10.1016/j.pain.2009.12.011 · Cited by 38 · see citing works
Determinants of Disability After Fingertip Injuries
Bot, A. G. J., Bossen, J. K. J., Mudgal, C. S., Jupiter, J. B., & Ring, D. (2014) · Psychosomatics · doi:10.1016/j.psym.2013.08.005 · Cited by 24 · see citing works
Developing an Intervention to Alter Catastrophizing in Persons With Fibromyalgia
Nelson, P. J., & Tucker, S. (2006) · Orthopaedic Nursing · doi:10.1097/00006416-200605000-00011 · Cited by 23 · see citing works
Dash, G. F., Feldstein Ewing, S. W., Murphy, C., Hudson, K. A., & Wilson, A. C. (2020) · Addictive Behaviors · doi:10.1016/j.addbeh.2020.106314 · Cited by 17 · see citing works
Hale, L., Devan, H., Davies, C., Dean, S. G., Dowell, A., Grainger, R., Gray, A. R., Hempel, D., Ingham, T., Jones, B., et al. (2021) · BMJ Open · doi:10.1136/bmjopen-2020-046376 · Cited by 13 · see citing works
Baranoff, J., Hanrahan, S. J., Kapur, D., & Connor, J. P. (2014) · Journal of Behavioral Medicine · doi:10.1007/s10865-013-9502-0 · Cited by 13 · see citing works
Verhaltenstherapeutische Konzepte in der Therapie chronischer Schmerzen
Kaiser, U., & Nilges, P. (2015) · Der Schmerz · doi:10.1007/s00482-014-1489-0 · Cited by 12 · see citing works
- Authors
- Asghari, A., & Nicholas, M. K.
- Affiliations
- Shahed University (IR)
- The University of Sydney (AU)
- Corresponding author
- Nicholas, Michael K.
- ORCID
- Nicholas, Michael K.
- Venue
- Pain
- Published
- 2001-10
- Volume
- 94
- Issue
- 1
- Pages
- 85-100
- ISSN
- 0304-3959 (ISSN-L)
- OpenAlex
- W2007224798
- Cited by
- 337
- References
- 60
- Citations by year
- 2026: 6 · 2025: 9 · 2024: 12 · 2023: 16 · 2022: 12 · 2021: 15 · 2020: 20 · 2019: 16 · 2018: 19 · 2017: 10 · 2016: 25 · 2015: 9 · 2014: 17 · 2013: 18 · 2012: 11
- FWCI
- 4.90
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Pain (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Health Sciences › Medicine › Pharmacology › Musculoskeletal pain and rehabilitation
- Health Sciences › Medicine › Pediatrics, Perinatology and Child Health › Pediatric Pain Management Techniques
- Life Sciences › Neuroscience › Cognitive Neuroscience › Pain Management and Placebo Effect
- Keywords
- pain self-efficacy, pain behavior, chronic pain, disability, pain catastrophizing, pain intensity, pain chronicity, depression, neuroticism
- MeSH terms
- Activities of Daily Living, Adolescent, Adult, Aged, Aged, 80 and over, Behavior, Cross-Sectional Studies, Female, Humans, Male, Middle Aged, Pain, Prospective Studies, Surveys and Questionnaires, Regression Analysis, Self Efficacy
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review