Table 1.
Summary of studies included in meta-analysis.
| Study author and year | Pain condition | Study design |
Country of study |
Pain group (N) |
Age (mean and SD) |
Sex (% female) |
Alexithymia measure |
Quality assessment (0–8) |
|---|---|---|---|---|---|---|---|---|
| Adult studies | ||||||||
| Ak (2004)1 | Mixed chronic pain | G, M | Turkey | 30 | 40.6 (11.4) | 83% | TAS-20 | 5 |
| Atagun (2012)3 | Fibromyalgia | C, M | Turkey | 57 | 40.9 (6.9) | 100% | TAS-20 | 5 |
| Baeza-Velasco(2012)4,* | Mixed chronic pain | C, G, M | France | 39 | 52.2 (8.9) | 100% | TAS-20 | 3 |
| Balaban (2012)8 | Headache | M | Turkey | 31 | 20.9 (1.7) | 81% | TAS-20 | 5 |
| Burger (2012)12,* | MSK | C, M | United States | 72 | 49.3 (15.6) | 79% | TAS-20 | 8 |
| Castelli (2012)16 | TMD | C, M | Italy | 45 | 38.9 (11.6) | 100% | TAS-20 | 4 |
| Castelli (2012)15 | Fibromyalgia | G, M | Italy | 55 | 52.8 (10.5) | 100% | TAS-20 | 4 |
| Cerutti (2016)17,*,† | Headache | M | Italy | 53 | 41.8 (3.9) | 53% | TAS-20 | 4 |
| Chang (2017)18,† | Chronic pain | G, M | Taiwan | 121 | 54.0 (15.6) | 9% | TAS-20 | 6 |
| Chang (2017)18,† | Fibromyalgia | G, M | Taiwan | 58 | 57.5 (15.8) | 71% | TAS-20 | 6 |
| Cologno (2005)19 | Headache | M | Italy | 35 | 38.0 (9.3) | 80% | TAS-20 | 3 |
| Di Tella (2017)23,* | Fibromyalgia | C, M | Italy | 159 | 52.5 (10.2) | 100% | TAS-20 | 6 |
| Duruk (2015)24,* | Fibromyalgia | C, G, M | Turkey | 35 | 41 (9.7) | 100% | TAS-20 | 6 |
| Esin (2017)26 | Headache | M | Russia | 137 | 40.8 (6.3) | 61% | TAS-26 | 3 |
| Evren (2006)27 | Fibromyalgia | C, M | Turkey | 51 | 37.2 (9.3) | 100% | TAS-20 | 6 |
| Fernandez (1989)28 | Autoimmune | G, M | India | 40 | 36.1 (11.3) | 65% | TAS-26 | 3 |
| Galli (2017)29,* | Headache | G, M | Italy | 80 | 44.7 (8.6) | 74% | TAS-20 | 5 |
| Ghiggia (2017)33,* | Fibromyalgia | C, G, M | Italy | 181 | 51.7 (10.2) | 100% | TAS-20 | 5 |
| Glaros (2005)34 | TMD | C, G, M | United States | 49 | 39.9 (12) | NR | TAS-20 | 5 |
| Gregory (2000)35 | Chronic pain | G, M | United States | 140 | 44.7 (11.2) | 75% | TAS-20 | 5 |
| Gregory (2005)36,† | Chronic pain | G, M | United States | 46 | NR | NR | TAS-20 | 6 |
| Gregory (2005)36,† | MSK | G, M | United States | 49 | NR | NR | TAS-20 | 7 |
| Gulec (2008)40,* | Fibromyalgia | C, M | Turkey | 75 | 43.6 (10.6) | 100% | TAS-20 | 7 |
| Haas (2013)41 | TMD | G | Germany | 20 | 40.6 (14.7) | 90% | TAS-26 | 7 |
| Hosoi (2010)43 | Autoimmune | C | United States | 129 | 52 (12.4) | 56% | TAS-20 | 6 |
| Huang (2016)44 | Mixed chronic pain | G, M | United States | 20 | 17 (NR) | 55% | TAS-20 | 5 |
| Huber (2009)45,* | Fibromyalgia | C, M | Italy | 68 | 43.4 (11.1) | 100% | TAS-20 | 5 |
| Jasinski (2016)47 | MSK | M | United States | 95 | 46.9 (9.7) | 52% | TAS-20 | 4 |
| Jerjes (2007)48 | Headache | G, M | United Kingdom | 51 | 40 (13) | 67% | TAS-20 | 5 |
| Jerlang (1997)49 | BMS | M | Denmark | 20 | 67 (NR) | 100% | TAS-26 | 4 |
| Johannsen (2017)51,* | Cancer | C, M | Denmark | 129 | 56.8 (9.1) | 100% | TAS-20 | 4 |
| Karahan (2016)53 | Autoimmune | G, M | Turkey | 148 | 52.6 (12.0) | 78% | TAS-20 | 5 |
| Kojima (2014)57,* | Autoimmune | C, M | Japan | 213 | 60 (12) | 82% | TAS-20 | 7 |
| Kosturek (1998)59 | MSK | M | United States | 50 | 43.6 (10.9) | 46% | TAS-20 | 6 |
| Kugu (2009)60 | Fibromyalgia | G, M | Turkey | 54 | 48.1 (8.1) | 100% | TAS-20 | 4 |
| Lumley (1997)68 | Chronic pain | C, G | United States | 30 | 40.4 (NR) | 70% | TAS-26 | 5 |
| Lumley (20 02)74,* | Myofascial | C, M | United States | 80 | 48.7 (11.8) | 75% | TAS-20 | 6 |
| Lumley (2005)72,† | Autoimmune | C, M | United States | 155 | 55 (NR) | 88% | TAS-20 | 5 |
| Lumley (2005)72,† | Headache | C, M | United States | 160 | 31.8 (NR) | 84% | TAS-20 | 5 |
| Makino (2013)75 | Mixed chronic pain | C, M | Japan | 128 | 52.3 (16.3) | 74% | TAS-20 | 7 |
| Margalit (2014)76,† | CRPS | C, M | Israel | 30 | 38.3 (14.3) | 40% | TAS-20 | 5 |
| Margalit (2014)76,† | MSK | C, M | Israel | 30 | 38.2 (12.5) | 40% | TAS-20 | 5 |
| Marino (2015)77 | BMS | C, G, M | Italy | 58 | 65.6 (10.5) | 79% | TAS-20 | 4 |
| Martinez (2015)78,* | Fibromyalgia | C | Spain | 100 | 48.4 (7.5) | 100% | TAS-20 | 4 |
| Melin (2010)79,* | Chronic pain | C, M | Sweden | 59 | 46 (NR) | 88% | TAS-20 | 4 |
| Melis (2014)80,* | Pelvic pain | C, M | Italy | 41 | 31.5 (6.4) | 100% | TAS-20 | 5 |
| Millard (1992)81 | Mixed chronic pain | C, M | United States | 194 | 42.8 (11.2) | 64% | TAS-26 | 5 |
| Mingarelli (2013)82 | TMD | C, M | Italy | 132 | 39.2 (13.6) | 85% | TAS-20 | 7 |
| Miyaoka (1996)83 | BMS | G | Japan | 50 | 55.8 (8.7) | 100% | TAS-26 | 2 |
| Montoro (2016)84,* | Fibromyalgia | C, G, M | Spain | 55 | 51.9 (8.8) | 100% | TAS-20 | 6 |
| Muftuoglu (2004)86 | Headache | G | Turkey | 50 | 32.1 (NR) | 64% | TAS-26 | 4 |
| Ozturk (2015)92 | Mastalgia | M | Turkey | 88 | 29.6 (8.2) | 100% | TAS-20 | 6 |
| Pecukonis (2009)96 | MSK | G | United States | 59 | 33.3 (11.9) | 100% | TAS-26 | 6 |
| Periacoba (2013)97 | Fibromyalgia | G | Spain | 120 | 50.9 (9.8) | 100% | TAS-20 | 5 |
| Pepe (2014)98,* | MSK | C, M | Italy | 40 | 44.8 (9.7) | 30% | TAS-20 | 6 |
| Porcelli (2014)99,* | IBS | C, M | Italy | 177 | 34.5 (11.7) | 71% | TAS-20 | 5 |
| Portincasa (2003)101 | IBS | G, M | Italy | 100 | 48 (2) | 27% | TAS-20 | 4 |
| Saariaho (2016)105 | Chronic pain | C, M | Finland | 83 | 49.5 (7.19) | 41% | TAS-20 | 5 |
| Sayar (20 04)107,† | Fibromyalgia | C , M | Turkey | 50 | 40.5 (8.8) | 100% | TAS-20 | 4 |
| Sayar (2004)107,† | Autoimmune | C , M | Turkey | 20 | 45.6 (14.9) | 100% | TAS-20 | 4 |
| Shibata (2014)109,* | Chronic pain | C, M | Japan | 439 | 61.1 (11) | 65% | TAS-20 | 6 |
| Sinikallio (2006)111 | MSK | M | Finland | 100 | 61.6 (11.2) | 58% | TAS-20 | 4 |
| Slavin-Spenny (2003)112 | Headache | M | United States | 147 | 22.1 (6) | 88% | TAS-20 | 7 |
| Steinweg (2011)113,† | Autoimmune | G, M | United States | 43 | 59.8 (13.7) | 9% | TAS-20 | 7 |
| Steinweg (2011)113,† | Fibromyalgia | G, M | United States | 48 | 54.1 (13.4) | 92% | TAS-20 | 7 |
| Tuzer (2011)120,† | Fibromyalgia | G, M | Turkey | 70 | 39.0 (7.9) | 100% | TAS-20 | 6 |
| Tuzer (2011)120,† | MSK | G, M | Turkey | 56 | 44.2 (9.3) | 100% | TAS-20 | 6 |
| Vadacca (2014)121,*,† | Autoimmune | C, M | Italy | 25 | 46 (11) | 100% | TAS-20 | 5 |
| Vadacca (2014)121,*,† | Autoimmune | C, M | Italy | 24 | 64 (10) | 100% | TAS-20 | 5 |
| Valkamo (2001)122 | Chest pain | M | Finland | 200 | 58.1 (9.4) | 34% | TAS-20 | 4 |
| van Middendorp (2008)123 | Fibromyalgia | C, G, M | Netherlands | 403 | 46.5 (12.3) | 100% | TAS-20 | 6 |
| Veehof (2011)124 | Fibromyalgia | M | Netherlands | 141 | 43.1 (10.9) | 92% | TAS-20 | 5 |
| Vieira (2013)125,* | Headache | C, M | Brazil | 39 | 43.6 (10.7) | 100% | TAS-26 | 6 |
| Villani (2005)126 | Headache | M | Italy | 42 | 35.7 (10.6) | 83% | TAS-20 | 3 |
| Villani (2010)127 | Headache | M | Italy | 465 | 34.7 (10.9) | 82% | TAS-20 | 3 |
| White (2011)130 | Chest pain | M | United States/ Israel | 229 | 50 (10.3) | 56% | TAS-20 | 6 |
| Wise (1994)131,† | Headache | M | United States | 61 | 37.8 (13.6) | NR | TAS-26 | 5 |
| Wise (1994)131,† | Headache | M | United States | 39 | 37.8 (13.6) | NR | TAS-26 | 5 |
| Yalug (2010)132 | Headache | C, M | Turkey | 300 | 37.4 (13.8) | 83% | TAS-20 | 7 |
| Yucel (2002)133 | Headache | G | Turkey | 105 | 33 (10) | 78% | TAS-26 | 6 |
| Zeng (2016)134 | Chronic pain | C | China | 147 | 34.9 (11.3) | 100% | TAS-20 | 4 |
| Zincir (2014)137 | Chest pain | G, M | Turkey | 51 | 33 (7.3) | 73% | TAS-20 | 6 |
| Youth studies: | ||||||||
| Cerutti (2016)17,*,† | Headache | C, M | Italy | 53 | 13.4 (2.4) | 57% | TAS-20 | 4 |
| Gatta (2011)31 | Headache | M, G | Italy | 32 | 11.2 (2) | 81% | AQC | 6 |
| Gatta (2015)32,† | Headache | M | Italy | 42 | 13.1 (2.4) | 57% | TAS-20 | 5 |
| Gatta (2015)32,† | Headache | M | Italy | 47 | 12.4 (2.3) | 77% | TAS-20 | 5 |
| Sayin (2007)108 | Mixed chronic pain | C | Turkey | 21 | 14.4 (2.6) | 33% | TAS-26 | 3 |
The study design column refers to included analyses relevant for the present meta-analysis: C, correlational; G, group difference; M, mean or prevalence.
*
Additional data provided by the author on personal request.
†
Represents data from 1 of 2 samples reported in the same article.
AQC, Alexithymia Questionnaire for Children; BMS, burning mouth syndrome; CPRS, complex regional pain syndrome; IBS, irritable bowel syndrome; MSK, musculoskeletal pain; NR, not reported; TMD, temporomandibular disorder.