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Table 2 Characteristics of review studies (k = 60)

From: A comprehensive meta-review of systematic reviews and meta-analyses on nonpharmacological interventions for informal dementia caregivers

Author (year)

No. of studies (search period)

Databases

Review method

Interventions

Major findingsa

Abrahams et al., 2018 [14]

22 RCT (up to Sept, 2015)

CINAHL, MEDLINE, PubMed, PsycINFO, OTseeker, EMBASE, Cochrane Library

Systematic review, meta-analysis

Multicomponent interventions

Burden (− 0.23), depression (− 0.21), self-reported health (0.24), social support (0.26)

Remarks: The authors claimed that only studies with CGs and CRs coresiding were included – a criterion clearly not met by the included studies. Moreover, not all interventions were clearly multicomponent.

Backhouse et al., 2017 [15]

14 RCT (up to 2015)

MEDLINE, Cochrane Library, EMBASE, PsycINFO; HMIC, SPP, ProQuest, ICTRP

Systematic review, meta-analysis

Care coordination delivered by a single professional

Burden (− 0.54)

ne: Mood, QoL, social support

Bernardo et al., 2018 [16]

8 RCT, NRSI and QS (2006–2015)

Web of Science, MEDLINE, CINAHL, PsycINFO and 4 other databases

Systematic review

Occupational therapeutic interventions with a focus on physical and social environmental modifications

↓ Burden, overload

↑ Sense of competence

Remarks: 1 study focused on institutionalized CRs was excluded.

Boots et al., 2014 [17]

12 RCT and NRSI (Jan, 1988-Jan, 2013)

PubMed, PsycINFO, CINAHL, Web of Science, Cochrane Library

Systematic review

Internet-based interventions

↓ Burden, depression

↑ Sense of competence, self-efficacy

Brodaty & Arasaratnam, 2012 [18]

23 RCT and NRSI (no period specified) on interventions with CR BPSD as outcome

MEDLINE, EMBASE, PubMed, PsycINFO, Scopus

Meta-analysis

Community-based non-pharmacological interventions for CR delivered with involvement of CG

Overall beneficial effect on a range of outcomes (e.g., burden, behavioral bother, self-efficacy, and confidence in managing BPSD) (0.15)

Chien et al., 2011 [19]

30 RCT and NRSI (1998–2009)

MEDLINE, Cochrane Library, PubMed

Systematic review, meta-analysis

Support groups and psychoeducationb

Burden (−0.23), depression (− 0.40), mental health (0.44)

Social outcomes (inc. social support, QoL and relationship with CR) (0.40)

Remarks: The theme of the review was support group interventions but > 80% of the interventions were psychoeducation groups.

Clarkson et al., 2018 [20]

68 RCT, NRSI and QS (up to Apr, 2014)

PubMed, Cochrane Library, PsycINFO, CINAHL and 2 other databases

Systematic review

Home support programs (inc. education, advice, behavioral management, psychological support, environmental modification, and care coordination)

↓ Burden

↑ Well-being

Remarks: 2 studies solely focused on CRs were excluded.

Collins & Kishita, 2018 [21]

12 RCT and NRSI (up to Dec, 2016)

PsycARTICLES, PsyINFO, MEDLINE Complete, Scopus, Web of Science, ProQuest

Meta-analysis

Mindfulness- and acceptance-based interventions

Depression (post-intervention − 0.98, follow-up − 0.71), burden (post-intervention − 0.66, follow-up − 0.53)

Cooper et al., 2007 [22]

24 RCT and NRSI (up to June, 2005) with CG anxiety as outcome

Allied and Complementary Medicine, British Nursing Index, CINAHL, EMBASE, MEDLINE, PsycINFO

Systematic review

Group CBT

↓ Anxiety

Behavioral management techniques

ne: Anxiety

Exercise interventions

ne: Anxiety

Multicomponent interventions

ne: Anxiety

Respite

ne: Anxiety

Relaxation and yoga

↓ Anxiety

Remarks: Psychoeducational interventions with CBT components were also included in the group CBT category. One of the two studies on relaxation and yoga [76] was in fact a psychoeducational program with 17% of the time allocated to progressive muscle relaxation and autogenic training.

Corbett et al., 2012 [23]

13 RCT (2001–2008)

Cochrane Library, EMBASE, MEDLINE, PsycINFO

Systematic review, meta-analysis

Provision of information and advice

ne: Burden/stress

QoL (0.36)

Dam et al., 2016 [24]

29 RCT, NRSI and QS from 39 articles (Jan, 1988-May, 2015

PubMed, PsycINFO, CINAHL, Web of Science, Cochrane Library

Systematic review

Support groups, befriending/peer support, mobilizing informal support networks, remote support interventionsB

↑ Social support, social satisfaction

ne: Burden, depression, self-esteem, QoL

Remarks: Family counseling programs were also included. Support interventions often omitted social support outcomes. Evidence on improved social support was derived mainly from qualitative studies. Based on quantitative studies, support groups had no effect, whereas remote support and network mobilization (inc. family counseling) interventions yielded mixed results.

Deeken et al., 2018 [25]

33 RCT (up to Aug, 2018)

PubMed, PsycINFO, Cochrane Library

Meta-analysis

Multimodal technology-based interventions

Burden (− 0.20), depression (− 0.31)

Inconclusive: Behavioral bother

Telephone intervention

ne: Burden

Depression (−0.24)

Computer/web-based interventions

ne: Burden, depression

All interventions combined

Burden (−0.13), depression (− 0.20)

Egan et al., 2018 [26]

8 RCT (up to Sept, 2016)

PubMed, Cochrane Library, CINAHL, Web of Science, PsycINFO, EMBASE

Systematic review

Internet-based interventions

↓ Depression, anxiety, stress

ne: Behavioral bother, knowledge, coping, QoL

Inconclusive: Self-efficacy

Eggenberger et al., 2013 [27]

4 RCT and NRSI (up to Jan, 2010)

MEDLINE, AMED, EMBASE, PsycINFO, CINAHL, Cochrane Library, Gerolit, Web of Science

Systematic review

Communication skills interventions

↓ Communication problems

↑ Skills and knowledge about communication

Remarks: 8 studies focused on institutionalized CRs were excluded.

Elvish et al., 2013 [28]

20 RCT, NRSI and QS (2005–2011) on psychological interventions

MEDLINE, PsycINFO, ERIC, PubMed

Systematic review

Psychoeducation with-skill building

↓ Depression

↑ Well-being, QoL

Multicomponent interventions

↓ Depression

↑ Social support, well-being

Technology-based

↓ Burden, depression

↑ Social support, well-being

Gallagher-Thompson & Coon, 2007 [29]

19 RCT and NRSI (1980–2005) on psychological interventions

MEDLINE, PsycINFO, ERIC, PubMed

Systematic review

Psychoeducation with skill building

Distress (−0.81)

CBT-based psychotherapy and counseling

Distress (−1.20)

Multicomponent interventions

Depression (−0.33)

Godwin et al., 2013 [30]

5 RCT from 8 articles (1990-May, 2012)

Medline, PsycINFO, EBSCO

Systematic review

Technology-driven interventions

↓ Depression, anxiety

ne: Social support

Remarks: 3 studies based on the same RCT were merged, and 1 meta-analytic study was removed.

Greenwood et al., 2016 [31]

4 RCT and NRSI (up to 2014)

MEDLINE, EMBASE, Cochrane Library, PsycINFO, CINAHL Plus and 2 other databases

Systematic review

Multicomponent interventions delivered by healthcare professionals

↓ Burden, depression

Remarks: All interventions were delivered by healthcare providers in general practice.

Hopkinson et al., 2019 [32]

25 RCT and NRSI (up to Jan, 2017)

MEDLINE, EMBASE, CINAHL, PsycINFO, Cochrane Library

Systematic review, meta-analysis

CBT

Depression (post-intervention − 0.34; follow-up − 0.99), stress (post-intervention − 0.36); effects driven by group programs only

ne: Anxiety, QoL

Remarks: Psychoeducation and multicomponent interventions with CBT components were included, as was a study testing psychodynamic group psychotherapy.

Hurley et al., 2014 [33]

8 RCT and NRSI (2004–2012)

PsycINFO, MEDLINE, Scopus, EMBASE

Systematic review

Meditation-based interventions

↓ Burden, depression

Jensen et al., 2015 [34]

7 RCT (Feb, 2010-Feb, 2013)

MEDLINE, EMBASE, PsycINFO, CINAHL, AgeLine, CENTRAL, ERIC

Systematic review, meta-analysis

Educational interventions

Burden (− 0.52), depression (− 0.37)

Inconclusive: QoL

Jütten et al., 2018 [35]

60 RCT and NRSI (Jan, 2002-Jan, 2017)

MEDLINE, PsycINFO, PsycARTICLES, Psychology and Behavioral Science Collections, Cochrane Library, EMBASE

Meta-analysis

Nonpharmacological interventions in general but excluding dyadic interventions, respite, case management and nursing interventionsb

Burden (− 0.20), stress (− 0.18), depression (− 0.19), QoL (0.36), sense of competence (0.31)

ne: Anxiety

Kaddour et al., 2019 [36]

14 RCT from 12 articles (up to July, 2017)

PsycINFO, MEDLINE, CINAHL, Scopus, Open Grey, ProQuest and 3 other databases

Meta-analysis

Low-intensity CBT-based interventions

Burden (− 0.53), distress (− 0.33), depression (− 0.27), anxiety (− 0.35)

Remarks: Psychoeducation and multicomponent interventions with CBT components were also included. One intervention [77] branded as psychoeducation in Kishita et al. [37] was classified as CBT-based intervention in this review.

Kishita et al., 2018 [37]

30 RCT (2006–2016)

MEDLINE, PsycINFO, Scopus, Cochrane Library

Systematic review, meta-analysis

Psychoeducation with-skill building

Burden (− 0.18)

ne: Depression, QoL

CBT-based psychotherapeutic interventions

ne: Burden

Depression (− 0.15), anxiety (− 0.38)

Remarks: Psychoeducation and multicomponent interventions with CBT components were also included.

Kor et al., 2018 [38]

5 RCT (1990–2016)

MEDLINE, CINAHL, Cochrane Library, PsycINFO, EMBASE, Web of Science

Systematic review, meta-analysis

Mindfulness-based interventions

Depression (− 0.62), stress (− 0.57)

Lamotte et al., 2017 [39]

3 RCT and NRSI (1990–2016)

PubMed, Cochrane Library, EMBASE, Google Scholar

Systematic review

Dyadic exercise interventions

↓ Burden (no effect in one RCT)

Remarks: 1 study without CG outcome was excluded.

Laver et al., 2017 [40]

38 RCT (2008-Oct, 2015)

MEDLINE, EMBASE, PsycINFO

Systematic review, meta-analysis

CG-only interventions

ne: Burden, depression, QoL

Dyadic interventions

ne: Burden, QoL

Depression (− 0.33)

All interventions combined

Behavioral bother (−0.26), QoL (0.24)

Remarks: 2 studies focused on institutionalized CRs were excluded. No significant differences were found between dyadic and CG-only interventions. Moreover, all interventions, inc. psychoeducation, support groups, family counseling, etc. were regarded as multicomponent by the authors. We dropped the term “multicomponent” to avoid confusion.

Li et al., 2013 [41]

8 RCT (up to July, 2011) on whether coping mediated intervention effects

EMBASE, MEDLINE, PsycINFO, Web of Science, Cochrane Library, CINAHL, AMED

Systematic review, meta-analysis

Group coping skills intervention

Depression (−0.91), dysfunctional coping (− 0.39)

Group coping skills intervention with behavioral activation

Depression (−0.30), positive coping (0.28), dysfunctional coping (− 0.26)

Remotely delivered intervention

↓ Depression (no pooled effect size)

ne: Coping

Inconclusive: Anxiety

Lins et al., 2014 [42]

11 RCT, NRSI and QS (May, 2011-Feb, 2013)

ALOIS, Cochrane Library

Systematic review, meta-analysis

Telephone counseling

Depression (−0.32)

ne: Burden, self-efficacy, social support

Telephone counseling with video sessions and a workbook

Inconclusive: self-efficacy

Liu et al., 2017 [43]

7 RCT (up to Apr, 2017)

Cochrane Library, MEDLINE, PsycINFO, EMBASE, CINAHL

Systematic review, meta-analysis

Mindfulness-based interventions

Depression (−0.58), stress (− 0.33), QoL (0.38)

ne: Burden, anxiety

Llanque & Enriquz, 2012 [44]

9 RCT and NRSI (2000–2011) on interventions for Hispanic CGs

Google Scholar, Social Gerontology, Health Source: Nursing/ Academic Edition, MEDLINE, PsycARTICLES, CINAHL, PubMed

Systematic review

Psychoeducation (with psychotherapeutic components), family therapy, telecommunication interventions, telephone support groups, multicomponent interventions, etc.b

↓ Depression

Remarks: 1 study without CG outcome was excluded.

Maayan et al., 2014 [45]

4 RCT (1989–2009)

ALOIS, Cochrane Library

Systematic review, meta-analysis

Respite service providing home support

ne: Depression

Remarks: It is noteworthy that respite was found to have no effect on any outcome but other outcomes are not listed here because they were assessed only once.

McKechnie et al., 2014 [46]

14 RCT and NRSI (Jan, 2000-Sept, 2012)

MEDLINE, PsycINFO, CINAHL Plus

Systematic review

Computer-mediated interventions

↓ Burden, depression, anxiety

ne: Self-reported health, social support

Inconclusive: Mental health, self-efficacy

Remarks: Reported results based on a subset of high- and medium-quality studies only.

Morris et al., 2018 [47]

18 RCT, NRSI and QS (from 2010)

CINAHL Plus, MEDLINE, PsycINFO

Systematic review

Communication skills training

↓ Burden, depression, anxiety

↑ Knowledge, communication skills

Nguyen et al., 2019 [48]

11 RCT and NRSI (period not specified)

MEDLINE, EMBASE, CINAHL, ProQuest, PsycINFO

Systematic review, meta-analysis

Communication skills training

↑ Communication

↓ Psycho-physiological states, inc. stress, burden, distress, depression and anxiety (pooled effect sizes not provided separately for informal CGs)

Remarks: 6 studies focused on institutionalized CRs and/or formal CGs were excluded.

Olazarán et al., 2010 [49]

91 RCT (up to Sept, 2008)

MEDLINE, PsycINFO, CINAHL, EMBASE, Lilacs, Cochrane Library

Systematic review, meta-analysis

Psychoeducation (individual sessions)

ne: Mood

Psychoeducation (group sessions)

ne: Mood, well-being

Support via electronic devices

ne: Mood

Multicomponent interventions

ne: Mood, well-being, QoL

Remarks: 108 studies of CR-focused interventions were excluded.

Orgeta et al., 2014 [50]

4 RCT (1997–2001)

MEDLINE, EMBASE, PubMed, PsycINFO, Scopus, Cochrane Library

Systematic review

Interventions for CG physical activity

Burden (−0.22)

ne: Depression, anxiety, stress

Parra-Vidales et al., 2017 [51]

7 NRSI and QS (2010–2015)

PubMed, PsycINFO, Scopus, SciELO, Psicodoc

Systematic review

Online psychoeducation

↓ Depression, stress

↑ Self-efficacy/competence, knowledge

ne: QoL

Petriwskyj et al., 2016 [52]

3 RCT, NRSI and QS (1990–2015)

CINAHL, PsycINFO, Web of Science, PubMed, EMBASE and 6 other databases

Systematic review

Interventions promoting resilience

ne: resilience

Piersol et al., 2017 [53]

36 RCT and NRSI (Jan, 2006-Apr, 2014)

MEDLINE, PsycINFO, CINAHL, OTseeker, Cochrane Library

Systematic review

Case management

↓ Burden

↑ Well-being

Group interventions

↓ Burden, distress

↑ Well-being, self-efficacy, mental health

CBT-based interventions

↓ Depression, anxiety, stress

Psychoeducation

↓ Burden, depression

↑ QoL, well-being, self-efficacy

Other single-component interventions (e.g., mindfulness-based, communication skills training, exercises programs)

↓ Burden/stress, depression, guilt

↑ Communication skills, well-being, mental health, hope, self-efficacy, relationship with CR

Remarks: 7 papers reporting systematic reviews or meta-analyses were excluded. The category “psychoeducation” was originally labeled idiosyncratically as “multicomponent psychoeducational intervention” but the word “multicomponent” is dropped here to avoid misunderstanding. Group interventions included support groups, family meetings, etc.

Pinquart & Sörensen, 2006 [12]

123 RCT and NRSI (1982–2005)

PsycINFO, MEDLINE, Ageline, PsyINDEX

Meta-analysis

Psychoeducation with CG active participation

Burden (−0.20), depression (− 0.36), SWB (0.21), ability/knowledge (0.55)

Psychoeducation-information only

Knowledge/ability (0.28)

ne: Burden, depression, SWB

CBT

Burden (−0.36), depression (− 0.70)

ne: SWB, knowledge/ability

Counseling/case management

Burden (−0.50)

ne: Depression, knowledge/ability, SWB

Support interventions

ne on outcomes (except one study with an effect on well-being)

Respite

Burden (−0.26), depression (− 0.12), SWB (0.27)

ne: Knowledge/ability

Multicomponent interventions

ne on any outcome (except for institutionalization of CR)

Miscellaneous (e.g., life review)

ne on any outcome

Remarks: 4 studies solely focused on CRs were excluded.

Powell et al., 2008 [54]

15 RCT and NRSI (up to Aug, 2007)

MEDLINE, EMBASE, CINAHL, PsycINFO, AMED

Systematic review

Technology-based interventions

↓ Burden, depression

Rausch et al., 2017 [55]

5 RCT and NRSI (up to Apr, 2016)

PubMed, PsycINFO, CINAHL

Systematic review

Dyadic interventions inc. group reminiscence, art viewing, art making; training individualized activities

↑ Mood, confidence (QS only)

Remarks: 2 studies without CG outcomes were excluded.

Schoenmakers et al., 2010 [56]

26 RCT and NRSI (1980–2007)

MEDLINE, EMBASE, Cochrane Library and 2 other databases

Systematic review, meta-analysis

Home care programs (inc. psychosocial interventions, respite, telephone support, and case management)

ne: Burden, depression (except for respite which was found to increase burden)

Scott et al., 2016 [57]

4 RCT and NRSI (from 1995)

PsycINFO, Cochrane Library, Scopus, MEDLINE

Systematic review, meta-analysis

Technology-based CBT

Depression (−0.21)

Remarks: Psychoeducation and multicomponent interventions with CBT components were also included.

Selwood et al., 2007 [58]

62 RCT and NRSI (up to July, 2003) on psychological interventions

Cochrane Library

Systematic review

Educational interventions

ne: Burden/stress, psychological health

Group training in coping skills

↓ Burden, depression

Individual training in coping skills

↓ Distress, depression

Group behavior management techniques (BMT)

ne: Burden, depression, or distress

Individual BMT (< 6 sessions)

ne Burden, depression, or distress

Individual BMT (≥6 sessions)

ne: Burden

↓ Depression (both post-intervention and follow-up)

Smith et al., 2014 [59]

4 RCT, NRSI, and QS (up to Jan, 2013)

MEDLINE, EMBASE, PsycINFO, Social Policy and Practice, CINAHL Plus and 2 other databases

Systematic review

Peer support and befriending delivered by volunteers on an one-on-one basis

ne: Mental health, loneliness

Smits et al., 2007 [60]

25 RCT and NRSI (1992–2005)

MEDLINE, PsycINFO, EBM Reviews-Cochrane Library

Systematic review

Dyadic interventions

Inconclusive: Burden, depression, mental health, competence

Tang et al., 2016 [61]

14 RCT, NRSI and mixed-method (1995–2014)

CINAHL EBM Reviews, EMBASE, MEDLINE, PsycINFO and 3 other databases

Systematic review

Psychosocial interventions with self-efficacy as outcome

↓ Burden

↑ Self-efficacy

Thompson et al., 2007 [62]

44 RCT and NRSI (Nov. 2003-Oct, 2005) on information and support interventionsb

Cochrane Library, MEDLINE, EMBASE, PsycINFO, CINAHL, SIGLE, ISTP, INSIDE and 17 other databases

Systematic review, meta-analysis

Technology-based support interventions

ne: Depression

Support groups

ne: Burden

Group psychoeducation

ne: Burden

Depression (−0.71)

Individual psychoeducation

ne: Depression, self-efficacy

Tretteteig et al., 2016 [63]

19 NRSI, QS or mixed-method (up to 2013)

PubMed, Norwegian Electronic Health Library, AMED, EMBASE, MEDLINE, PsycINFO

Systematic review

Day care services

↓ Burden, overload, depression

↑ Perceived support

Inconclusive: Well-being

Tyack & Camic, 2017 [64]

7 RCT, NRSI, QS and mixed-method (period not specified)

PsycINFO, ASSIA, MEDLINE, CINAHL, Cochrane Library

Systematic review

Touchscreen (interactive computer-based) interventions

Inconclusive: Burden, well-being, relationship with CR

Remarks: 9 studies without informal CGs were excluded.

Vandepitte et al., 2016 [65]

17 RCT and NRSI (up to Jan, 2015)

PubMed, Web of Science

Systematic review

Respite

Inconclusive: Burden

ne: Stress

Vandepitte et al., 2016 [66]

53 RCT and NRSI (up to Mar, 2015)

Web of Science, PubMed

Systematic review

Psychoeducation

↓ Burden, depression

↑ Self-efficacy

Respite

Inconclusive: Burden

Occupational therapy interventions

↑ Self-efficacy

CBT

↓ Depression, dysfunctional thoughts

Remarks: Psychoeducation and multicomponent interventions with CBT components were also included in the CBT category.

Vernooij-Dassen et al., 2011 [67]

11 RCT (up to Apr, 2009)

Cochrane Library, MEDLINE, EMBASE, PsycINFO, CINAHL and 2 other databases

Systematic review, meta-analysis

Cognitive reframing

Depression (−0.24), anxiety (− 0.21), stress/distress (− 0.24)

ne: Burden, behavioral bother, coping/self-efficacy

Remarks: CBT and psychoeducation were both included and analyzed together.

Waller et al., 2017 [68]

34 RCT and NRSI (Jan, 1990-Dec, 2016)

MEDLINE, EMBASE, CINAHL, Cochrane Library

Systematic review

Computer (inc. tablet, website, e-mail or mobile app) interventions

↓ Burden/stress, depression

↑ Mental health, knowledge, positive aspects of caregiving

Telephone (inc. text messaging, telehealth, videophone) interventions

Inconclusive: Burden, depression, mental health, managing BPSD

ne: Social support, self-efficacy, health, self-care

Multimodal (computer plus telephone) interventions

Inconclusive: Burden, depression, self-efficacy

Weinbrecht et al., 2016 [69]

33 RCT (2005–2014)

MEDLINE, EMBASE, CENTRAL, PsycINFO, PsyINDEX

Meta-analysis

A range of intervention types (e.g., education, counseling, support group, communication skills, environmental modification, care coordination)B

Depression (post-intervention −0.13, follow-up − 0.29)

Williams et al., 2019 [70]

34 RCT (1999–2018) with burden as outcome

MEDLINE, PsycINFO, CINAHL

Systematic review, meta-analysis

Multicomponent interventions

Inconclusive: Burden

Education/skills-based interventions

Inconclusive: Burden

Support and counselling

Inconclusive: Burden

Physical activity

ne: Burden

Wilson et al., 2017 [71]

3 RCT and NRSI (from 1995-Sept, 2016)

MEDLINE, CINAHL Plus, EBSCO, PubMed, EMBASE, PsycINFO and 4 other databases

Systematic review, meta-analysis

Interventions targeting CG grief

↓ Grief (2 out of 3 studies)

Ying et al., 2018 [72]

15 RCT (up to Jan, 2017)

PubMed, EMBASE, Cochrane Library, Web of Science, EBSCO, PsycINFO

Systematic review

Multicomponent interventions

↑ Competence, knowledge, coping

Inconclusive: Burden

Remarks: Some CG-only interventions showed larger effects than dyadic programs.

  1. For the number of intervention studies included in each review, we eliminated those that did not report informal CG outcomes and made a remark beneath each study. Pooled effect sizes were not available for some meta-analytic studies as they were not reported by the study authors for various reasons. BPSD behavioral and psychological symptoms of dementia, CBT cognitive-behavioral therapy, CG caregiver, CR care-recipient; NRSI non-randomized study of intervention, QoL quality of life, QS qualitative study, RCT randomized controlled trial, SWB subjective well-being; ↑ = enhanced; ↓ = reduced
  2. aNumeral in parenthesis refers to standardized or weighted mean difference when a significant effect was found; ne = no effect observed through either quantitative or qualitative synthesis. In terms of meta-analytic results, only pooled effects with p < 0.05 are reported as significant in the table, disregarding the interpretation provided in the original review article
  3. bEffects were discussed or analyzed without differentiating types of intervention, or without categorizing interventions