Comparison of five conditioned pain modulation paradigms and influencing personal factors in healthy adults.
Journal
European journal of pain (London, England)
ISSN: 1532-2149
Titre abrégé: Eur J Pain
Pays: England
ID NLM: 9801774
Informations de publication
Date de publication:
01 2021
01 2021
Historique:
received:
03
02
2020
revised:
14
08
2020
accepted:
16
09
2020
pubmed:
24
9
2020
medline:
27
4
2021
entrez:
23
9
2020
Statut:
ppublish
Résumé
Conditioned pain modulation (CPM) methods are experimental procedures to assess presumed descending nociceptive modulatory pathways. Various CPM-methods are currently used, making the comparison of results difficult. The aim of this study was to compare five conditioning stimuli and to evaluate the influencing effects of personal factors on CPM-efficacy. 101 healthy pain-free adults (50 males, 51 females) participated in this cross-sectional study with repeated measures design. The CPM-method consisted of hot water immersion (46°C, HWI), cold pressor test (12°C, CPT), cold pack application, and single and double ischemic occlusion as conditioning stimuli in randomized order. Pressure pain threshold was used as test stimulus at the mm. trapezius and quadriceps for all CPM-protocols. All CPM-protocols resulted in effective CPM, although cold pack application revealed smaller CPM-magnitudes compared to all other methods at both muscles, except single ischemic occlusion at the m. quadriceps. A smaller CPM-effect at the m. trapezius was shown when CPM was provoked by single ischemic occlusion compared to the CPT. Chronic stress, gender, attentional focus, age, physical activity and perceived pain are all influencing factors, in various conditioning stimuli at the mm. trapezius and quadriceps. CPT and HWI seem to be the most appropriate conditioned pain modulation paradigms for research settings, while single and double ischemic occlusion seem to be more useful for clinical settings. Influencing factors to be considered are gender, age, stress, physical activity, perceived pain and attentional focus to the conditioning stimulus, but depend on the test site and exerted method. Hot water immersion, cold pressor test, and single and double ischemic occlusion result in comparable CPM-effects at the mm. trapezius and quadriceps. Anti-nociceptive effects of the cold pack are mainly a result of attention towards the cold pack. Chronic stress, attentional focus towards the conditioning stimulus and perceived pain of the conditioning stimulus influenced the anti-nociceptive effects at the m. trapezius. Gender and level of physical activity influenced the anti-nociceptive effects with the other methods at the m. quadriceps.
Sections du résumé
BACKGROUND
Conditioned pain modulation (CPM) methods are experimental procedures to assess presumed descending nociceptive modulatory pathways. Various CPM-methods are currently used, making the comparison of results difficult. The aim of this study was to compare five conditioning stimuli and to evaluate the influencing effects of personal factors on CPM-efficacy.
METHODS
101 healthy pain-free adults (50 males, 51 females) participated in this cross-sectional study with repeated measures design. The CPM-method consisted of hot water immersion (46°C, HWI), cold pressor test (12°C, CPT), cold pack application, and single and double ischemic occlusion as conditioning stimuli in randomized order. Pressure pain threshold was used as test stimulus at the mm. trapezius and quadriceps for all CPM-protocols.
RESULTS
All CPM-protocols resulted in effective CPM, although cold pack application revealed smaller CPM-magnitudes compared to all other methods at both muscles, except single ischemic occlusion at the m. quadriceps. A smaller CPM-effect at the m. trapezius was shown when CPM was provoked by single ischemic occlusion compared to the CPT. Chronic stress, gender, attentional focus, age, physical activity and perceived pain are all influencing factors, in various conditioning stimuli at the mm. trapezius and quadriceps.
CONCLUSIONS
CPT and HWI seem to be the most appropriate conditioned pain modulation paradigms for research settings, while single and double ischemic occlusion seem to be more useful for clinical settings. Influencing factors to be considered are gender, age, stress, physical activity, perceived pain and attentional focus to the conditioning stimulus, but depend on the test site and exerted method.
SIGNIFICANCE
Hot water immersion, cold pressor test, and single and double ischemic occlusion result in comparable CPM-effects at the mm. trapezius and quadriceps. Anti-nociceptive effects of the cold pack are mainly a result of attention towards the cold pack. Chronic stress, attentional focus towards the conditioning stimulus and perceived pain of the conditioning stimulus influenced the anti-nociceptive effects at the m. trapezius. Gender and level of physical activity influenced the anti-nociceptive effects with the other methods at the m. quadriceps.
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
243-256Informations de copyright
© 2020 European Pain Federation - EFIC®.
Références
Ainsworth, B. E., Bassett, D. R., Jr, Strath, S. J., Swartz, A. M., O'Brien, W. L., Thompson, R. W., Jones, D. A., Macera, C. A., & Kimsey, C. D. (2000). Comparison of three methods for measuring the time spent in physical activity. Medicine and Science in Sports and Exercise, 32, S457-464. https://doi.org/10.1097/00005768-200009001-00004
Arendt-Nielsen, L., Sluka, K. A., & Nie, H. L. (2008). Experimental muscle pain impairs descending inhibition. Pain, 140, 465-471. https://doi.org/10.1016/j.pain.2008.09.027
Basbaum, A. I., Bautista, D. M., Scherrer, G., & Julius, D. (2009). Cellular and molecular mechanisms of pain. Cell, 139, 267-284. https://doi.org/10.1016/j.cell.2009.09.028
Boonstra, A. M., Schiphorst Preuper, H. R., Balk, G. A., & Stewart, R. E. (2014). Cut-off points for mild, moderate, and severe pain on the visual analogue scale for pain in patients with chronic musculoskeletal pain. Pain, 155, 2545-2550. https://doi.org/10.1016/j.pain.2014.09.014
Booth, M. (2000). Assessment of physical activity: An international perspective. Research Quarterly for Exercise and Sport, 71, S114-120.
Brugha, T. S., & Cragg, D. (1990). The list of threatening experiences: The reliability and validity of a brief life events questionnaire. Acta Psychiatrica Scandinavica, 82, 77-81.
Butler, R. K., & Finn, D. P. (2009). Stress-induced analgesia. Progress in Neurobiology, 88, 184-202. https://doi.org/10.1016/j.pneurobio.2009.04.003
Campbell, C. M., France, C. R., Robinson, M. E., Logan, H. L., Geffken, G. R., & Fillingim, R. B. (2008). Ethnic differences in diffuse noxious inhibitory controls. The Journal of Pain, 9, 759-766. https://doi.org/10.1016/j.jpain.2008.03.010
Cathcart, S., Winefield, A. H., Rolan, P., & Lushington, K. (2009). Reliability of temporal summation and diffuse noxious inhibitory control. Pain Research and Management, 14, 433-438.
Chalaye, P., Devoize, L., Lafrenaye, S., Dallel, R., & Marchand, S. (2013). Cardiovascular influences on conditioned pain modulation. Pain, 154, 1377-1382. https://doi.org/10.1016/j.pain.2013.04.027
Cormier, S., Piche, M., & Rainville, P. (2013). Expectations modulate heterotopic noxious counter-stimulation analgesia. The Journal of Pain, 14, 114-125. https://doi.org/10.1016/j.jpain.2012.10.006
Craig, C. L., Marshall, A. L., Sjostrom, M., Bauman, A. E., Booth, M. L., Ainsworth, B. E., Pratt, M., Ekelund, U., Yngve, A., Sallis, J. F., & Oja, P. (2003). International physical activity questionnaire: 12-country reliability and validity. Medicine and Science in Sports and Exercise, 35, 1381-1395. https://doi.org/10.1249/01.MSS.0000078924.61453.FB
Crews, J. C., Cahall, M., & Behbehani, M. M. (1994). The neurophysiologic mechanisms of tourniquet pain. The activity of neurons in the rostroventral medulla in the rat. Anesthesiology, 81, 730,73610.1097/00000542-199409000-00027.
Daenen, L., Nijs, J., Cras, P., Wouters, K., & Roussel, N. (2014). Changes in pain modulation occur soon after whiplash trauma but are not related to altered perception of distorted visual feedback. Pain Practice, 14, 588-598. https://doi.org/10.1111/papr.12113
Daenen, L., Nijs, J., Roussel, N., Wouters, K., Van Loo, M., & Cras, P. (2013). Dysfunctional pain inhibition in patients with chronic whiplash-associated disorders: An experimental study. Clinical Rheumatology, 32, 23-31. https://doi.org/10.1007/s10067-012-2085-2
Defrin, R., Tsedek, I., Lugasi, I., Moriles, I., & Urca, G. (2010). The interactions between spatial summation and DNIC: Effect of the distance between two painful stimuli and attentional factors on pain perception. Pain, 151, 489-495. https://doi.org/10.1016/j.pain.2010.08.009
Fechir, M., Schlereth, T., Kritzmann, S., Balon, S., Pfeifer, N., Geber, C., Breimhorst, M., Eberle, T., Gamer, M., & Birklein, F. (2009). Stress and thermoregulation: Different sympathetic responses and different effects on experimental pain. European The Journal of Pain, 13, 935-941. https://doi.org/10.1016/j.ejpain.2008.11.002
Foxen-Craft, E., & Dahlquist, L. M. (2017). Brief submaximal isometric exercise improves cold pressor pain tolerance. Journal of Behavioral Medicine, 40, 760-771. https://doi.org/10.1007/s10865-017-9842-2
France, C. R., & Suchowiecki, S. (1999). A comparison of diffuse noxious inhibitory controls in men and women. Pain, 81, 77-84.
Granot, M., Weissman-Fogel, I., Crispel, Y., Pud, D., Granovsky, Y., Sprecher, E., & Yarnitsky, D. (2008). Determinants of endogenous analgesia magnitude in a diffuse noxious inhibitory control (DNIC) paradigm: Do conditioning stimulus painfulness, gender and personality variables matter? Pain, 136, 142-149. https://doi.org/10.1016/j.pain.2007.06.029
Grashorn, W., Sprenger, C., Forkmann, K., Wrobel, N., & Bingel, U. (2013). Age-dependent decline of endogenous pain control: Exploring the effect of expectation and depression. PLoS One, 8, e75629. https://doi.org/10.1371/journal.pone.0075629
Graven-Nielsen, T., Izumi, M., Petersen, K. K., & Arendt-Nielsen, L. (2017). User-independent assessment of conditioning pain modulation by cuff pressure algometry. European The Journal of Pain, 21, 552-561. https://doi.org/10.1002/ejp.958
Hackett, J., Naugle, K. E., & Naugle, K. M. (2020). The decline of endogenous pain modulation with aging: A meta-analysis of temporal summation and conditioned pain modulation. J Pain, 21(5-6), 514-528. https://doi.org/10.1016/j.jpain.2019.09.005
Hendriks, A. O., van de Willige, G. (1990). Langdurige moeilijkheden gemeten volgens zelfbeoordelingsvragenlijst en semi-gestructureerd interview: Een theoretische en empirische vergelijking. Gedrag & gezondheid.
Hermann, R., Biallas, B., Predel, H. G., & Petrowski, K. (2019) Physical versus psychosocial stress: effects on hormonal, autonomic, and psychological parameters in healthy young men. Stress 22, 103-11210.1080/10253890.2018.1514384.
Hermans, L., Van Oosterwijck, J., Goubert, D., Goudman, L., Crombez, G., Calders, P., & Meeus, M. (2016). Inventory of personal factors influencing conditioned pain modulation in healthy people: A systematic literature review. Pain Practice, 16, 758-769. https://doi.org/10.1111/papr.12305
Hoegh, M., Seminowicz, D. A., & Graven-Nielsen, T. (2019). Delayed effects of attention on pain sensitivity and conditioned pain modulation. European Journal of Pain, 23, 1850-1862. https://doi.org/10.1002/ejp.1458
Imai, Y., Petersen, K. K., Mørch, C. D., & Arendt, N. L. (2016) Comparing test-retest reliability and magnitude of conditioned pain modulation using different combinations of test and conditioning stimuli. Somatosensory and Motor Research 33, 169-177. 10.1080/08990220.2016.1229178.
Joels, M., & Baram, T. Z. (2009). The neuro-symphony of stress. Nature Reviews Neuroscience, 10, 459-466. https://doi.org/10.1038/nrn2632
Kakigi, R. (1994). Diffuse noxious inhibitory control. Reappraisal by pain-related somatosensory evoked potentials following CO2 laser stimulation. Journal of the Neurological Sciences, 125, 198-205. 10.1016/0022-510x(94)90036-1.
Kennedy, D. L., Kemp, H. I., Ridout, D., Yarnitsky, D., & Rice, A. S. (2016). Reliability of conditioned pain modulation: A systematic review. Pain, 157, 2410-2419. https://doi.org/10.1097/j.pain.0000000000000689
Khan, J., Korczeniewska, O., Benoliel, R., Kalladka, M., Eliav, E., & Nasri-Heir, C. (2018). Age and gender differences in mechanically induced intraoral temporal summation and conditioned pain modulation in healthy subjects. Oral Surgery, Oral Medicine, Oral Pathology, and Oral Radiology, 126, 134-141. https://doi.org/10.1016/j.oooo.2018.03.021
Kinser, A. M., Sands, W. A., & Stone, M. H. (2009). Reliability and validity of a pressure algometer. The Journal of Strength and Conditioning Research, 23, 312-314. https://doi.org/10.1519/jsc.0b013e31818f051c
Kwak, S. G., & Kim, J. H. (2017). Central limit theorem: The cornerstone of modern statistics. Korean Journal of Anesthesiology, 70, 144-156. https://doi.org/10.4097/kjae.2017.70.2.144
Ladouceur, A., Tessier, J., Provencher, B., Rainville, P., & Piche, M. (2012). Top-down attentional modulation of analgesia induced by heterotopic noxious counterstimulation. Pain, 153, 1755-1762. https://doi.org/10.1016/j.pain.2012.05.019
Lariviere, M., Goffaux, P., Marchand, S., & Julien, N. (2007). Changes in pain perception and descending inhibitory controls start at middle age in healthy adults. Clinical Journal of Pain, 23, 506-510. https://doi.org/10.1097/AJP.0b013e31806a23e8
Larra, M. F., Schilling, T. M., Röhrig, P., & Schächinger, H. (2015) Enhanced stress response by a bilateral feet compared to a unilateral hand Cold Pressor Test. Stress, 18, 589-596. 10.3109/10253890.2015.1053452.
Lautenbacher, S., Kunz, M., & Burkhardt, S. (2008). The effects of DNIC-type inhibition on temporal summation compared to single pulse processing: Does sex matter? Pain, 140, 429-435. https://doi.org/10.1016/j.pain.2008.09.019
Le Bars, D., Dickenson, A. H., & Besson, J. M. (1979). Diffuse noxious inhibitory controls (DNIC). II. Lack of effect on non-convergent neurones, supraspinal involvement and theoretical implications. Pain, 6, 305-327. 10.1016/0304-3959(79)90050-2.
Leone, C., & Truini, A. (2019). The CPM effect: functional assessment of the diffuse noxious inhibitory control in humans. Journal of Clinical Neurophysiology, 36, 430-436. https://doi.org/10.1097/wnp.0000000000000599
Lewis, G. N., Heales, L., Rice, D. A., Rome, K., & McNair, P. J. (2012). Reliability of the conditioned pain modulation paradigm to assess endogenous inhibitory pain pathways. Pain Research and Management, 17, 98-102.
Lewis, G. N., Rice, D. A., & McNair, P. J. (2012). Conditioned pain modulation in populations with chronic pain: A systematic review and meta-analysis. The Journal of Pain, 13, 936-944. https://doi.org/10.1016/j.jpain.2012.07.005
Locke, D., Gibson, W., Moss, P., Munyard, K., Mamotte, C., & Wright, A. (2014). Analysis of meaningful conditioned pain modulation effect in a pain-free adult population. The Journal of Pain, 15, 1190-1198. https://doi.org/10.1016/j.jpain.2014.09.001
Logan, H., Lutgendorf, S., Rainville, P., Sheffield, D., Iverson, K., & Lubaroff, D. (2001). Effects of stress and relaxation on capsaicin-induced pain. The Journal of Pain, 2, 160-170. https://doi.org/10.1054/jpai.2001.21597
Marouf, R., Caron, S., Lussier, M., Bherer, L., Piche, M., & Rainville, P. (2014). Reduced pain inhibition is associated with reduced cognitive inhibition in healthy aging. Pain, 155, 494-502. https://doi.org/10.1016/j.pain.2013.11.011
McCracken, L. (1997). “Attention” to pain in persons with chronic pain: A behavioral approach. Behavior Therapy, 28, 271-284. 10.1016/S0005-7894(97)80047-0.
McNeil, D. W., Kennedy, S. G., Randall, C. L., Addicks, S. H., Wright, C. D., Hursey, K. G., & Vaglienti, R. (2018). Fear of pain questionnaire-9: Brief assessment of pain-related fear and anxiety. European Journal of Pain, 22, 39-48. https://doi.org/10.1002/ejp.1074
Meeus, M., Ickmans, K., Struyf, F., Hermans, L., Van Noesel, K., Oderkerk, J., Declerck, L. S., Moorkens, G., Hans, G., Grosemans, S., & Nijs, J. (2013). Does acetaminophen activate endogenous pain inhibition in chronic fatigue syndrome/fibromyalgia and rheumatoid arthritis? A double-blind randomized controlled cross-over trial. Pain Physician, 16, E61-70.
Moont, R., Pud, D., Sprecher, E., Sharvit, G., & Yarnitsky, D. (2010). 'Pain inhibits pain' mechanisms: Is pain modulation simply due to distraction? Pain, 150, 113-120. https://doi.org/10.1016/j.pain.2010.04.009
Nahman-Averbuch, H., Nir, R. R., Sprecher, E., & Yarnitsky, D. (2016). Psychological factors and conditioned pain modulation: A meta-analysis. Clinical Journal of Pain, 32, 541-554. https://doi.org/10.1097/ajp.0000000000000296
Naugle, K. M., Fillingim, R. B., & Riley, J. L., 3rd (2012). A meta-analytic review of the hypoalgesic effects of exercise. The Journal of Pain, 13, 1139-1150. https://doi.org/10.1016/j.jpain.2012.09.006
Naugle, K. M., & Riley, J. L., 3rd (2014). Self-reported physical activity predicts pain inhibitory and facilitatory function. Medicine and Science in Sports and Exercise, 46, 622-629. https://doi.org/10.1249/MSS.0b013e3182a69cf1
Nir, R. R., Granovsky, Y., Yarnitsky, D., Sprecher, E., & Granot, M. (2011). A psychophysical study of endogenous analgesia: The role of the conditioning pain in the induction and magnitude of conditioned pain modulation. European Journal of Pain, 15, 491-497. https://doi.org/10.1016/j.ejpain.2010.10.001
Nir, R. R., & Yarnitsky, D. (2015). Conditioned pain modulation. Curr Opin Support Palliat Care, 9, 131-137. https://doi.org/10.1097/spc.0000000000000126
Nuwailati, R., Curatolo, M., LeResche, L., Ramsay, D. S., Spiekerman, C., & Drangsholt, M. (2019). Reliability of the conditioned pain modulation paradigm across three anatomical sites. Scand. The Journal of Pain, https://doi.org/10.1515/sjpain-2019-0080
Ohrbach, R., & Gale, E. N. (1989). Pressure pain thresholds in normal muscles: Reliability, measurement effects, and topographic differences. Pain, 37, 257-263. https://doi.org/10.1016/0304-3959(89)90189-9
Olango, W. M., & Finn, D. P. (2014). Neurobiology of stress-induced hyperalgesia. Current Topics in Behavioral Neurosciences, 20, 251-280. https://doi.org/10.1007/7854_2014_302
Oono, Y., Nie, H., Matos, R. L., Wang, K., & Arendt-Nielsen, L. (2011). The inter- and intra-individual variance in descending pain modulation evoked by different conditioning stimuli in healthy men. Scand Journal of Pain, 2, 162-169. https://doi.org/10.1016/j.sjpain.2011.05.006
Osman, A., Barrios, F. X., Kopper, B. A., Hauptmann, W., Jones, J., & O'Neill, E. (1997). Factor structure, reliability, and validity of the Pain Catastrophizing Scale. Journal of Behavioral Medicine, 20, 589-605.
Parr, J. J., Borsa, P. A., Fillingim, R. B., Tillman, M. D., Manini, T. M., Gregory, C. M., & George, S. Z. (2012). Pain-related fear and catastrophizing predict pain intensity and disability independently using an induced muscle injury model. The Journal of Pain, 13, 370-378. https://doi.org/10.1016/j.jpain.2011.12.011
Pud, D., Granovsky, Y., & Yarnitsky, D. (2009). The methodology of experimentally induced diffuse noxious inhibitory control (DNIC)-like effect in humans. Pain, 144, 16-19. https://doi.org/10.1016/j.pain.2009.02.015
Quevedo, A. S., & Coghill, R. C. (2007). Attentional modulation of spatial integration of pain: Evidence for dynamic spatial tuning. Journal of Neuroscience, 27, 11635-11640. https://doi.org/10.1523/jneurosci.3356-07.2007
Rezaii, T., & Ernberg, M. (2010). Influence of oral contraceptives on endogenous pain control in healthy women. Experimental Brain Research, 203, 329-338. https://doi.org/10.1007/s00221-010-2246-y
Riley, J. L., 3rd, Cruz-Almeida, Y., Staud, R., & Fillingim, R. B. (2020). Age does not affect sex effect of conditioned pain modulation of pressure and thermal pain across 2 conditioning stimuli. Pain Reports, 5, e796. https://doi.org/10.1097/pr9.0000000000000796
Roelofs, J., Peters, M. L., Muris, P., & Vlaeyen, J. W. (2002). Dutch version of the Pain Vigilance and Awareness Questionnaire: Validity and reliability in a pain-free population. Behavior Research and Therapy, 40, 1081-1090.
Rosmalen, J. G., Bos, E. H., & de Jonge, P. (2012). Validation of the Long-term Difficulties Inventory (LDI) and the List of Threatening Experiences (LTE) as measures of stress in epidemiological population-based cohort studies. Psychological Medicine, 42, 2599-2608. https://doi.org/10.1017/s0033291712000608
Schulz, A., Lass-Hennemann, J., Sütterlin, S., Schächinger, H., & Vögele, C. (2013). Cold pressor stress induces opposite effects on cardioceptive accuracy dependent on assessment paradigm. Biological Psychology, 93, 167-174. https://doi.org/10.1016/j.biopsycho.2013.01.007
Skovbjerg, S., Jørgensen, T., Arendt-Nielsen, L., Ebstrup, J. F., Carstensen, T., & Graven-Nielsen, T. (2017). Conditioned pain modulation and pressure pain sensitivity in the adult danish general population: The DanFunD study. The Journal of Pain, 18, 274-284. https://doi.org/10.1016/j.jpain.2016.10.022
Smith, A., & Pedler, A. (2018). Conditioned pain modulation is affected by occlusion cuff conditioning stimulus intensity, but not duration. European Journal of Pain, 22, 94-102. https://doi.org/10.1002/ejp.1093
Sullivan, M. J. L., Bishop, S. R., & Pivik, J. (1995). The pain catastrophizing scale: Development and validation. Psychological Assessment, 7, 524-532. https://doi.org/10.1037/1040-3590.7.4.524
Tousignant-Laflamme, Y., & Marchand, S. (2009). Excitatory and inhibitory pain mechanisms during the menstrual cycle in healthy women. Pain, 146, 47-55. https://doi.org/10.1016/j.pain.2009.06.018
Traxler, J., Hanssen, M. M., Lautenbacher, S., Ottawa, F., & Peters, M. L. (2019). General versus pain-specific cognitions: Pain catastrophizing but not optimism influences conditioned pain modulation. European Journal of Pain, 23, 150-159. https://doi.org/10.1002/ejp.1294
Umeda, M., Lee, W., Marino, C. A., & Hilliard, S. C. (2016). Influence of moderate intensity physical activity levels and gender on conditioned pain modulation. Journal of Sports Sciences, 34(5), 467-476. 10.1080/02640414.2015.1061199.
Urbaniak, G., & Plous, S. (2013). Research Randomizer (Version, 4.0), 4.0.
Vaegter, H. B., Fehrmann, E., Gajsar, H., & Kreddig, N. (2020). Endogenous modulation of pain: The role of exercise, stress, and cognitions in humans. Clinical Journal of Pain, 36, 150-161. https://doi.org/10.1097/ajp.0000000000000788
Vaegter, H. B., Handberg, G., & Graven-Nielsen, T. (2014). Similarities between exercise-induced hypoalgesia and conditioned pain modulation in humans. Pain, 155, 158-167. https://doi.org/10.1016/j.pain.2013.09.023
Vaegter, H. B., Petersen, K. K., Mørch, C. D., Imai, Y., & Arendt-Nielsen, L. (2018). Assessment of CPM reliability: Quantification of the within-subject reliability of 10 different protocols. Scandinavian Journal of Pain, 18, 729-737. https://doi.org/10.1515/sjpain-2018-0087
van Wijk, G., & Veldhuijzen, D. S. (2010). Perspective on diffuse noxious inhibitory controls as a model of endogenous pain modulation in clinical pain syndromes. The Journal of Pain, 11, 408-419. https://doi.org/10.1016/j.jpain.2009.10.009
Vassend, O., & Knardahl, S. (2004). Cardiovascular responsiveness to brief cognitive challenges and pain sensitivity in women. European Journal of Pain, 8, 315-324. https://doi.org/10.1016/j.ejpain.2003.10.006
Waller, R., Straker, L., O'Sullivan, P., Sterling, M., & Smith, A. (2015). Reliability of pressure pain threshold testing in healthy pain free young adults. Scandinavian Journal of Pain, 9, 38-41. https://doi.org/10.1016/j.sjpain.2015.05.004
Yarnitsky, D., Bouhassira, D., Drewes, A. M., Fillingim, R. B., Granot, M., Hansson, P., Landau, R., Marchand, S., Matre, D., Nilsen, K. B., Stubhaug, A., Treede, R. D., & Wilder-Smith, O. H. (2015). Recommendations on practice of conditioned pain modulation (CPM) testing. European Journal of Pain, 19, 805-806. https://doi.org/10.1002/ejp.605
Yarnitsky, D., Granot, M., & Granovsky, Y. (2014). Pain modulation profile and pain therapy: Between pro- and antinociception. Pain, 155, 663-665. https://doi.org/10.1016/j.pain.2013.11.005