What is the independent, dependent, and extraneous variables in this study?

What is the research design.

METHODS

This randomized clinical trial used a parallel design. Women

whose screenings were positive for depressive or anxious

symptoms were enrolled in this study and were randomly assigned

to either an intervention group, in which they received

an 8-week mindfulness intervention, or a control group, in

which they received routine care over the same time. Data

were collected before and after the intervention using self report

questionnaires to determine changes in mindfulness

and the symptoms of anxiety and depression and to evaluate

the feasibility and acceptability of the intervention during

pregnancy.

This study was approved by the institutional review board

of the hospital (no. 20170118).Written informed consent was

obtained from all subjects, who were assured that participation was

voluntary, that they were free to exit the study at any

time, and that all data collected were confidential.

Recruitment of Participants

This study was carried out at Women's Hospital School of

Medicine at Zhejiang University. Recruitment was conducted

in the obstetrics clinic of the hospital fromApril to June 2018.

Women who went to the hospital between 24 and 30 weeks'

gestation for regular antepartum examinations were screened

for depressive or anxious symptoms using the Patient Health

Questionnaire (PHQ-9) and Generalized Anxiety Disorder

Scale (GAD-7). The nurses distributed leaflets to women with

mild or moderate symptoms of anxiety or depression (GAD-

7 score _4 or PHQ-9 score _4) to explain the purpose of the

study and the aim of the mindfulness intervention, namely,

improving management of emotions and the ability to cope

with stress, and to invite them to participate in the study. Researchers

interviewed interested women in the waiting room

to determine their eligibility. Women who met the criteria

were provided with more details of the study, questions were

answered, and written consent was obtained. Nurses regularly

assessed themental state of women who did not participate in

the study, asked their family to observe changes in their emotions,

and referred them to receive psychotherapywhen severe

psychological problems were found.

The inclusion criteria were women aged more than 18

years, 24 to 30 weeks' gestation, low-risk pregnancy at the

start of the intervention, internet access, fluent in Chinese

and able to complete the questionnaires, and elevated depressive

or anxious symptoms as determined by either a PHQ-9

score of more than 4 or a GAD-7 score of more than 4.30,31

The exclusion criteria were history or current diagnosis of

a psychosomatic disease (physical symptoms or illness that

results from interplay of psychosocial and physiologic processes,

such as hypertension, diabetes mellitus, or asthma),

current substance abuse, previous participation in psychological

therapy or a stress reduction program, history of suicide

attempts, current use of any psychoactive drug, and a high

level of depression (PHQ-9 score _14) or anxiety (GAD-7

score _14).30,31 Women who had regular mind-body practice

(yoga, meditation, or mindfulness practice) were also excluded

from the study.

G*Power software was used to calculate the number of

participants required. Previous 8-week mindfulness interventions

in pregnantwomen showed medium-to-large effect sizes

for anxiety (Cohen's d, 0.48-0.66) and depression (Cohen's d,

0.42-0.75).20,32,33 Thus, at an effect size of d=0.58, and allowing

for a 25% attrition rate, the total number of participants

required was 125 for a power of 0.8.34

PROCEDURE

After determining eligibility, participants were randomized

into the mindfulness intervention or control group using the

block randomization method. The randomization sequence

was computer generated, and group assignment was done

by staff not associated with the study using opaque, sealed

envelopes. Participants were asked to complete the online

questionnaires to assess their levels of mindfulness, depressive

symptoms, and anxiety symptoms before and after the

intervention.

Intervention Group

The 8-week mindfulness intervention program drew on theoretical

constructions of mindfulness, attention monitoring,

and acceptance theory and comprised the following elements

of mindfulness-based stress reduction therapy,25,35 adapted

for pregnant women: 1) paying attention to the intended target

and discriminating present experiences and 2) adopting

an accepting attitude toward physical and emotional experiences.

Through mindfulness practice, participants could increase nonjudgmental awareness of momentary experience.

The specific aims of the programwere to help participants improve

their skills coping with stress during pregnancy and to

alleviate depression and anxiety symptoms.

The intervention was conducted on theWechat platform,

which is a Chinese mobile application that allows interactive

learning between instructors and learners. The mindfulness

intervention program included 4 sessions, each approximately

40 minutes, over the course of 8 weeks. All sessions

were recorded and were uploaded to theWechat platform for

participants to access.Additional text, pictures, and audios related

to the course were available for participants to review.

The content of each session included a brief review of the

mindfulness practice from the previous session, an introduction

to the central theme of the current mindfulness practice,

and assignment of homework for the upcoming week. Table 1

summarizes the details of the program.

All women in the intervention group joined the Wechat

interaction group to share experiences, discuss barriers to

practicing mindfulness, and interact with other participants

and the researchers at any time. All questions and consultations

related to the intervention or pregnancy were addressed

within 48 hours. During the intervention, nurses contacted

all participants throughWechat video or telephone to address

specific training problems and to understand their experience

of mindfulness practice by asking them to describe their feelings

about the mindfulness practice and its perceived impact

on their daily life. Based on this interaction, the nurses determined

whether participants exhibited severe symptoms of

depression and anxiety. Anyone who exhibited severe symptoms

was referred for further psychological assessment and

treatment.

A multidisciplinary research team including a psychologist,

a midwife, and 2 nurses developed the intervention

program. Three experts, including a psychologist, an obstetrics

expert, and a clinical nursing specialist validated the

content of the intervention. The intervention program was

principally conducted by 2 nurses and themidwife, but a psychologist

with experience treating perinatal mental disorders

who also has received faculty training in mindfulness-based

cognitive therapy, supervised the project and reviewed the

content of the sessions. The nurse with experience leading

mindfulness groups recorded all sessions. The midwife and

another nurse were responsible for Wechat group management,

including correcting inappropriate information,

encouraging homework practice, and tracking training

adherence.

Control Group

Participants in the control group received routine care. Specifically,

nurses and clinicians provided these women with antepartum

health education related to childbirth, breastfeeding,

nutrition, and parenting. As these women exhibited mild

ormoderate symptoms of depression or anxiety, they were referred

to receive psychological counselling if necessary. The

nurses provided emotion management skills through lectures

and taught the women in the group to identify symptoms of

depression and anxiety. Women in the control group were

also enrolled in a Wechat group to interact with each other.

The nurses regularly contacted them to answer pregnancyrelatedquestions.

Anyone exhibiting severe depressive or anxious

symptoms was referred for psychotherapy. To address

ethical concerns, participants in the control group were eligible

for one day of mindfulness training at no cost at the end

of the study.

Outcome Measures and Data Collection

Adherence to the intervention was examined through documentation

of completed sessions. Participants were asked to

report to the researchers when completing each session. In

addition, the intervention application automatically recorded

which women logged into each session. Participants were

also asked to report weekly how much time they spent on

mindfulness practice per week. Moreover, a self-report questionnaire

was sent to participants at the end of the final

session. The questionnaire comprised structured and openended

questions about the experience of mindfulness meditation,

the use of mindfulness skills, and satisfaction with

the program. Demographic and maternal health characteristics

were collected at baseline, including age, employment status,

education level, gestational week, marital status, and other

information.

Symptoms of depression were assessed using the PHQ-9,

which is based on 9 diagnostic criteria for depression taken

from the Diagnostic and Statistical Manual of Mental Disorders,

Fourth Edition, Text Revision. PHQ-9 scores range

from 0 to 27; cutoffs are 5, 10, 15, and 20 for mild, moderate,

moderately severe, and severe depression, respectively.

The Chinese version of the PHQ has been validated for use in

pregnant women (Cronbach's _ = 0.86).31

The level of general anxietywas assessedusing theGAD-7

scale, a 7-item self-report questionnaire. Scores on the GAD-

7 range from 0 to 21, and each item is assigned a score of 0

to 3; cutoffs are 5, 10, and 15 for mild, moderate, and severe

anxiety, respectively. Cronbach's _ for the Chinese version is

0.86.30

The level of mindfulness was measured using the Five

Facets ofMindfulness Questionnaire (FFMQ), a 39-item selfreport

questionnaire with 5 mindfulness domains: observing,

describing, acting with awareness, nonjudgment, and nonreactivity.

The observing domain corresponds to attentionmonitoring,

and the nonjudgment and nonreactivity domains correspond

to acceptance.25 The items are rated on a 5-point

Likert-type scale from 1 (never true) to 5 (always true); total

scores range from 0 to 195, and higher scores indicate greater

mindfulness. The Chinese version of the FFMQ has good internal

consistency and test-retest reliability (Cronbach's _ =

0.81).36

Participants who did not return a completed questionnaire

within 3 days were reminded to do so by telephone. Researchers

blinded to the group allocation collected the outcome

data and checked the questionnaires immediately after

collection. If any problems were apparent, they guided participants

to complete or revise the answers.

Data Analysis

SPSS software (version 20.0; IBM Corporation, Armonk,

NY) was used to analyze the data, which were cross-checked for verification, and normality was assessed

with the Kolmogorov-Smirnov test. Analyses were conducted

based on an intention-to-treat approach, which

means that participants were analyzed in accordance with

their initial group assignment. The multiple imputation

method was used for missing data. To determine whether

the assumption that data were missing at random was violated,

a sensitivity analysis was performed. All data were

summarized with descriptive statistics (mean and SD or

number and percent). Student's t test and the chi-square

test were employed to examine differences in the baseline

characteristics between the 2 groups. The independent t

test was used to compare the scores for the 3 instruments,

and the paired-samples t test was used to test for withingroup

differences. A P value less than .05 was considered

significant.

Journal

RESULTS

A total of 642 women completed the screening questionnaires,

and 224 women had positive screenings for depressive

or anxious symptoms. Within this group, 43 were excluded

because they did not meet the additional eligibility

criteria, and 58 declined to participate. Thus, 123 women

(62 in the intervention group and 61 in the control group)

were enrolled in this study. Nine participants in the intervention

group were lost to follow-up; among these,

5 dropped out of the study because of the burden of

daily mindfulness practice, and 4 did not complete the

postintervention assessment. Eight participants in the control

group did not complete the postintervention assessment.

In addition, one woman in the intervention group and 3 in

the control group discontinued the intervention because of an

increase in depressive symptoms (see Figure 1 for the CONSORT

flow chart). Therefore, 52 women remained in the intervention

group, and 50 remained in the control group. No

significant differences in the demographic or maternal health

variables were observed between these groups (Table 2).

Participant Feedback

In the intervention group, 52 (83.9%) women completed at

least 3 sessions. However, the adherence to dailymindfulness

practice was fairly low. The mean (SD) number of mindfulness

meditations per week was 3.25 (1.45) times over the 8-

week intervention. The mean (SD) number of minutes spent

on meditation each time was 21.23 (16.16) min.

Table 3 shows the results of participant feedback. All

women learned the skills of attention monitoring (ie, being

aware of the body sensations, maintaining a focus on the

present, labelling and distinguishing internal and external experiences).

In contrast, it was relatively more difficult for participants

to learn the ability to tolerate discomfort and to

adopt an accepting attitude toward all experiences.Overall, 45

(86.5%) participants reported that the mindfulness intervention

was beneficial, 28 (53.8%) felt relaxed and calm during

themindfulness meditation, 21 (40.4%)women found that the

mindfulness practice helped them become fully aware of fetal

movement, and 12 (23.1%) reported that the intervention

relieved discomfort and allowed them to be more energetic.

However, daily mindfulness practice was also reported to be

onerous. Some women reported that learning to maintain an

accepting attitude was challenging.

Anxiety and Depression Symptoms

Table 4 shows the descriptive statistics for all outcome variables

(PHQ-9, GAD-7, and FFMQscores) before and after the

intervention, aswell as the statistical results of the comparison

between the 2 groups of the outcomes after the intervention

for the intention-to-treat samples. The data for the per-protocol

samples are available from the authors. No significant

differences in the baseline PHQ-9 or GAD-7 scores were

observed between the 2 groups. In the intervention group, the

mean scores of the PHQ-9 andGAD-7 before the intervention

were 5.98 and 5.52, respectively, indicating mild symptoms of

depression and anxiety; these scores decreased significantly

to 3.58 (PHQ-9) and 2.97 (GAD-7) at the end of the intervention,

indicating no symptoms (t=6.218, P_.001; t=5.422, P

_.001, respectively). However, no changes in the PHQ-9 and

GAD-7 scores were observed in women in the control group

when scores before versus after intervention were compared.

Postintervention scores of both PHQ-9 and GAD-7 were

significantly lower in the intervention group than in the in the intervention group had no symptoms of depression

or anxiety after the intervention (41 and 49 women with

no symptoms of depression and anxiety, respectively) compared

with women in the control group (22 and 26 women,

respectively; Table 5).

Mindfulness

No differences in FFMQ scores or scores for any of the subscales

were observed between the 2 groups at baseline. FFMQ

scores and scores for the observing subscale (corresponding to

attention monitoring) and the nonjudgment and nonreactivity

subscales (corresponding to acceptance) significantly improved

in the intervention group over the 8-week mindfulness

intervention (mean score increases of 7.47, 2.18, 2.05, and

2.99, respectively), but there were no changes in the scores for

subscales in the intervention group.

DISCUSSION

We investigated the effects of an 8-week mindfulness intervention

that focused on attention monitoring and acceptance

in pregnant women. The results showed that participants

in the intervention group exhibited greater declines in

symptoms of depression and anxiety compared with those

in the control group, as well as significant improvement in

mindfulness.

One of the goals of this studywas to test the feasibility and

acceptability of a Wechat-based mindfulness intervention

for pregnant women. Previous studies examining the online

delivery of mindfulness interventions showed high attrition

rates. For example, Krusche et al reported a 21% completion

rate in a sample of 107 participants enrolled in an online

mindfulness training. The researchers considered that this

attrition rate was due to the lack of peer support from other

participants, a low level of communication with researchers,

and the absence of instructors to consult about problems.2 In the present study, the Wechat-based intervention format

was applied to partly compensate for these shortcomings, as

it provided a platform for women to access the mindfulness

course and also facilitated ongoing interaction between

researchers and participants. The retention rate (83.87%) for

this study was comparable to those in other studies using

face-to-face mindfulness interventions, which have reported

completion rates of more than 80%.28,33 However, it was still

difficult for instructors to dynamically observe participants'

status in their mindfulness practice and communicate with

them in real time. The results show that a small portion

of the participants did not master the mindfulness skills to

relieve discomfort and to adopt an accepting attitude toward

all experiences. In addition, the daily homework was too

onerous for some participants. Therefore, it might be of

value to explore barriers to homework practice, to emphasize

training in mindfulness acceptance, and to increase communication

between instructors and participants in the future

research.

Results from preintervention-to-postintervention analyses

in preliminary studies showed that participation in a

mindfulness intervention was related to the reduction in

maternal depression and anxiety.37,38 However, systematic

reviews that pooled results of the randomized controlled

studies have found no differences in postintervention outcomes

of depression and anxiety between the mindfulness

intervention group and the control group.37,39 This finding

appears to be contrary to other randomized control studies on

the effectiveness of the mindfulness-based interventions that

evaluated adult nonpregnant individuals in which mediumto-

large positive effects on depression and anxiety have been

found.40,41 It should be noted that, the majority of studies of

the mindfulness interventions during pregnancy focused on

the improvement of well-being outcomes in healthy women,

rather than treating those with elevated symptoms. It could

be that the effects of the mindfulness intervention were not

noticeable in women with low baseline levels of depression

and anxiety.37,38 Moreover, the components of mindfulness

intervention programs included in the reviews were variable

based on the aim of the study. For example, they often comprised

less frequent mindfulness practice and fewer sessions,

thus increasing heterogeneity. In addition, the reviews were

limited by methodologies that included small sample sizes,

various ranges of self-report measurement, significant loss to

follow-up, and lack of generalization, making it difficult to

draw definitive conclusions.37

In this study, no differences were observed in the control

group on scores for depression and anxiety. Consequently,

it may be difficult to improve the mental health of women

through antepartum health education within the framework

of pregnancy care, because such care focuses on labor and

childbirth education rather than on emotion management.

In addition to routine pregnancy care, women in the control

group did receive extra assistance from the researchers,

which could independently relieve depression and anxiety.

Still, intention-to-treat analyses confirmed that the intervention

group experienced fewer depressive and anxious symptoms

compared with the control group after the intervention.

Taken as a whole, these findings demonstrate the value

of implementing mindfulness intervention for women under

stress and suggest the need for more robust evidence in this

field.

The mindfulness intervention program in this study was

developed to help women tolerate discomfort and cope with

negative emotions by training them in attention monitoring

and acceptance. Participants in the intervention group

showed significantly increased observing, nonjudgment, and

nonreactivity subscale scores after the intervention.Most participants

reported learning to monitor internal and external

experiences in an accepting way. A randomized mixedmethods

trial conducted in New Zealand also found that

mindfulness training fostered an internalized locus of selfacceptance

that could help women reduce their dependency

on others for well-being.42

The best dosage ofmindfulness intervention for pregnant

women have not been determined. Most studies have conducted

8-week or 6-week mindfulness programs, with each

sessionvarying from2 to3hours.However,one studydemonstrated

that 2 weeks of daily mindfulness training along with

a booster session was sufficient to develop sufficient mindfulness

skill to reduce the biological impact of stress.24 In addition,

several studies have investigated other specific components

of mindfulness intervention; for example, a 10-week

prenatal yoga practice aimed to significantly increase nonjudgmental

attention to the present experience as a means

of treating maternal depression.43 Another used mindful eating

to help with better management of overeating during

pregnancy.44 In light of these findings, further studies should

be conducted to explore the development of a mindfulnessbased

intervention program(eg, length, duration, and content

of the program) based on the target population and expected

outcomes.

This study has some limitations. The present study assessed

depressive and anxious symptoms using self-report

questionnaires rather than a diagnostic interview. Although

these scales have high sensitivity and specificity in pregnant

women, participants in the intervention group could have

shown greater reductions in self-reported symptoms because

they were not blinded to the group allocation. The positive

outcomes from mindfulness training could also be related to

greater attention fromand interaction with researchers among

intervention group than among control group members, resulting

in biased results. In addition, only one follow-up was

conducted after the intervention. The results of this study revealed

short-termeffects but did not clarify the long-termoutcomes

of the intervention. Therefore, further research should

use an active control group matched in intensity with the intervention

group and should investigate the long-term effects

of mindfulness intervention.

Generalization of the findings may be limited, as this

study only enrolled women without pregnancy complications

or severe symptoms of depression or anxiety. Moreover,

these women expressed interest in the mindfulness intervention,

which may have increased their motivation to

adhere to the mindfulness practice. Therefore, more studies

are needed to better understand which pregnant women

could and could not benefit from an online mindfulness

intervention.

Journal CLINICAL IMPLICATIONS

The current study excludedwomen with high scores for symptoms

of anxiety or depression (PHQ-9 score _14 or GAD-7

score _14). The efficacy of the mindfulness intervention for

treating depression and anxiety remains to be confirmed in

subsequent research. However, given that universal depression

and anxiety screening is recommended as part of routine

care during pregnancy, it is necessary to test novel interventions

that may be more effective than current treatment options

for treating maternal depression and anxiety. This study

suggested that a mindfulness interventionmay be a promising

technique for relieving symptoms of depression and anxiety

during pregnancy. We recommend that a mindfulness intervention

constitute part of the prenatal psychological care to

improvemental health, supplementing in-person psychotherapy

for women with depression and anxiety. Clinical staff

should teach women to self-identify the symptoms of depression

and anxiety. Those involved in public policy should facilitate

the treatment of women with depression and anxiety,

including those who lack resources for expensive and intensive

psychological care.

CONCLUSION

This study investigated the effectiveness of an antenatal mindfulness

training program in reducing depressive and anxious

symptoms and improving mindfulness skills of attention

monitoring and acceptance. The findings contribute to evidence

for the feasibility and acceptability of online mindfulness

interventions during pregnancy. Mindfulness intervention

could constitute part of the psychological care provided

to pregnant women. More studies are needed to examine the

efficacy of a mindfulness intervention for treating depression

and anxiety.