Table 2.

CBT and comparison group information.

Author year	Groups	Type of CBT	CBT sessions	CBT duration (W)	Comparison type
Balser 1997	CBT + UC vs. UC	Face-to-face	12 sessions ∗ 120 min	12	UC: various forms of medical treatment such as pain medication, nerve blocks, transcutaneous electrical stimulation, and physical therapy, but not surgery.
Beth 2021	CBT vs. PE CBT vs. ER	Face-to-face	8 sessions ∗ 120 min	8	PE: pain education, matched to empowered relief on 4 key factors: duration, structure, format, and site. ER: empowered relief consists of a single-session, 2-hour pain class that includes pain neuroscience education, mindfulness principles, and CBT skills.
Buhrman 2004	CBT vs. WL	Internet-based	Webpages	8	WL: nonspecific treatment control had been used instead of a waiting list.
Carpenter 2012	CBT vs. WL	Internet-based	Webpages	3	WL: nonspecific treatment control had been used instead of a waiting list.
Cherkin 2016	CBT vs. UC, CBT vs. MBSR	Face-to-face	2 sessions ∗ 120 min ∗ 8 W	8	UC: free to seek whatever treatment but no MBSR training or CBT. MBSR: mindfulness-based stress reduction, a program does not focus specifically on a particular condition such as pain.
Christiansen 2010	CBT + UC vs. UC	Face-to-face	2 sessions ∗ 30 min	3	UC: standard outpatient back pain program.
Godfrey 2020	ACT + PT vs. PT	Face-to-face and telephone call	3 sessions ∗  (60 min ∗ 2 + 20 min)	6	PT: usual physical therapy including manual therapy techniques.
Gould 2020	CBT + placebo vs. placebo	Face-to-face	6 sessions (1 ∗ 90 min + 5 ∗ 60 min)	8	Placebo: a dose of benztropine mesylate 0.125 mg daily was chosen.
Harris 2017	BI vs. BI + CBT vs. BI + PE	Face-to-face	7 sessions ∗ 90 min	12	BI: brief intervention, a brief cognitive, clinical examination program addressing pain and fear avoidance. PE: Group physical exercise consisted of strength and endurance training and relaxation.
Ivar brox 2003	Surgery vs. CBT + PT	Face-to-face	NA	12	Surgery: posterolateral fusion with transpedicular screws of the L4–L5 segment and/or the L5–S1 segment. PT: customarily prescribed physiotherapy, including exercises.
Johnson 2007	CBT + UC vs. UC	Face-to-face and leaflet	8 sessions ∗ 120 min	6	UC: received no further intervention and continued to be treated as usual.
Khan 2014	CBT + exercise vs. exercise	Face-to-face	3 sessions ∗ 12 ∗ ? min	12	Exercise: general exercise protocol under the supervision of a physical therapist.
Monticone 2013	CBT + exercise vs. exercise	Face-to-face	5 ∗ 60 min + 12 ∗ 60 min	54	Exercise: general exercise protocol under the supervision of a physical therapist.
Newton 1995	CBT vs. EMGBF vs. WL	Face-to-face	5 ∗ 90 min	4	EMGBF: electromyographic biofeedback, consisted firstly of a psychoeducational session, then introduced to the pain-tension-pain cycle. WL: nonspecific treatment control had been used instead of a waiting list.
Petrozzi 2019	CBT + PT vs. PT	Internet-based	5 modules, online-based	8	PT: included manual therapy in combination with other modalities such as advice, education, and exercise.
Pincus 2015	CBT vs. PT	Face-to-face	8 sessions ∗ 50 min	12	PT: physiotherapy was delivered as usual within services, with the stipulation that it included at least 60% exercise.
Reme 2016	BI + CBT vs. BI	Audiotaped	7 sessions ∗ ? min	8	BI: brief intervention, a brief cognitive, clinical examination program based on a noninjury model addressing pain and fear avoidance, where return to normal activity and work is the main goal.
Rutledge 2018a	CBT vs. UC	Text-based	12 sessions (1 ∗ 120 min + 11 ∗ 30 min)	8	UC: controlled for nonspecific benefits of therapy.
Rutledge 2018b	CBT vs. UC	Telephone-based	12 sessions (1 ∗ 120 min + 11 ∗ 30 min)	8	UC: controlled for nonspecific benefits of therapy.
Schweikert 2006	CBT + UC vs. UC	Face-to-face	6 sessions ∗ 90 min	3	UC: standardized conventional 3-week inpatient rehabilitation program consisting of daily physiotherapy, massage of the spinal region, electrotherapeutical measures, 1-hour seminar regarding back training, twice-daily exercise program.
Smeets 2006	CBT vs. PT, CBT vs. WL	Face-to-face	18 sessions, total: 11.5 ∗ 60 min	10	PT: aerobic training on a bicycle and strength and endurance training. WL: not allowed to participate in diagnostic or therapeutic procedures because of their CLBP.
Turner 2016	CBT vs. UC, CBT vs. MBSR	Face-to-face	2 sessions ∗ 120 min ∗ 8 W	8	UC: free to seek whatever treatment but no MBSR training or CBT. MBSR: mindfulness-based stress reduction: a program does not focus specifically on a particular condition such as pain.

UC: usual care; PE: pain education; ER: empowered relief; WL: waiting-list; PT: physical therapy; BI: brief intervention; MBSR: mindfulness-based stress reduction; EMGBF: electromyographic biofeedback.