Methods

Randomised controlled trial

Participants

Number randomised: 41 infants with moderate risk for neuromotor disabilities were initially randomised (25 intervention, 16 control).

Number analysed: 28 were analysed (13 control: 9 male, 4 female; 15 intervention: 9 male, 6 female).

Dropouts/withdrawals: 10 intervention (6 did not follow protocol, 3 voluntarily withdrew, 1 diagnosed with genetic disorder), 3 control (1 unable to schedule data collection, 1 diagnosed with genetic disorder, 1 received Botox injections on multiple occasions).

All participants entered the study when they were able to take 10 steps on the treadmill in 1 minute (minimum age: 6 months; maximum age: 13 months, to guarantee minimum length of TM training).

Of the included infants, 18 were low‐birth‐weight (< 1500 g), 21 had low gestational age (< 32 weeks), 22 had a brain insult, 15 received prolonged ventilator use, 11 were from multiple births.

Mean age (SD): control 9.0 (1.4) months; intervention 9.7 (1.3) months.

Ethnicity: no information available.

Interventions

Control:

1. All infants continued with standard physical therapy (twice a week) without treadmill intervention, prescribed by the local Early Intervention programme.

Intervention:

1. Home‐based treadmill training, 8 min/day, 5 days/week, belt speed: 0.2 m/s, beginning with 1 minute training intervals and then taking a brief rest before continuing the training until 8 minutes were completed. As the child's supported treadmill stepping increased over time, parents were encouraged to gradually increase the training beyond 1‐minute intervals before resting.

2. Treadmill training continued until the infant was observed walking 3 independent steps over ground.

3. The amount of treadmill use in minutes was recorded (gauge attached to the side of treadmill) during monthly visits to the infants.

Outcomes

1. Treadmill step frequency;

2. Treadmill step quality (type of foot contact);

3. Age at onset of independent walking;

4. Modified Ashworth Scale;

5. Bayley Scales of Infant and Toddler Development (motor and mental subscales);

6. GMFM.

From unpublished data obtained from Chen 2008:

1. Step length;

2. Step velocity;

3. Cadence;

4. Step width;

Notes

Country: USA.

Funding source: This work was funded by a research grant from the U.S. Office of Special Education & Rehabilitative Services (H324C040016) awarded to the first author.

Comment: This study was initially recorded as Chen 2008 since, at the time of the original review, data were unpublished but obtained from the author. For the update, the trial was published and, at this point, for Angulo‐Barroso 2013, we included unpublished data from Chen and published data on the actual paper.

Risk of bias

Bias

Authors' judgement

Support for judgement

Random sequence generation (selection bias)

Low risk

Comment: Eligible participants were randomised to either treadmill training group or the control group by a statistician using a computer programme for group allocation, considering 3 stratification factors: age, gender, and birth weight. All participants were assigned an ID, which was entered into the computer by a statistician to conduct the participant's allocation.

Allocation concealment (selection bias)

Low risk

Comment: The information (see support for judgement above) was provided to the project coordinator and home assessment personnel but maintained the laboratory assessors blind to group allocation.

Blinding of participants and personnel (performance bias)
All outcomes

High risk

Comment: No blinding.

Blinding of outcome assessment (detection bias)
All outcomes

Low risk

Comment: The laboratory assessors were blind to group allocation.

Incomplete outcome data (attrition bias)
Experimental group 1

Unclear risk

Treadmill training:

1. 25 allocated

2. 10 discontinued intervention for the following reasons:

   1. 6 did not follow the protocol

   2. 3 voluntarily withdrew

   3. 1 was diagnosed with genetic disorder

3. 15 were analysed

Control:

1. 16 allocated

2. Data collected from 15; 1 unable to schedule for data collection

3. 2 were excluded from the analysis for the following reasons:

   1. 1 diagnosed with genetic disorder

   2. 1 received multiple occasions of Botox injections

4. 13 were analysed

Selective reporting (reporting bias)

Low risk

Comment: No evidence of reporting bias.

Other bias

Unclear risk

Comment: None noted.

Methods

Randomised controlled trial (cross‐over design: AAB, ABA).

Participants

Number randomised: 20 children were screened and 12 children met the inclusion criteria, but only 8 children joined the study program; they were control and crossed over to intervention. They all had a diagnosis of spastic cerebral palsy (two females and six males).

Number analysed: 8 children (2 female, 6 male).

Dropouts/withdrawals: none.

Mean age (SD): not reported; age range from 3.5 to 6.3 years.

Ethnicity: not reported.

Interventions

Control (A):

1. Regular therapeutic treatment (NDT: mat exercises for range of motion, stretching, strengthening, and motor function activities. Gross motor activities included changing positions, lie to sit, sit to stand, and standing;

2. 2 to 3 times/wk, 30 min/session.

Intervention (B):

1. Treadmill treatment (Treadmill training with Body Weight Support, TBWS);

2. 20 min/session, 2 to 3 sessions/wk, for a total of 12 weeks.

Outcomes

1. GMFM, total score;

2. Gait speed;

3. Gait stride length;

4. Gait double‐limb support.

Notes

Country: Taiwan.

Funding source: This study was supported by NSC 92‐2218‐E‐006‐003 and through a collaboration of National Cheng Kung University and Chi Mei Medical Center.

Risk of bias

Bias

Authors' judgement

Support for judgement

Random sequence generation (selection bias)

Unclear risk

Comment: The children were divided equally into 2 groups and randomly assigned to the schedules.

Allocation concealment (selection bias)

High risk

Comment: Cross‐sectional trial.

Blinding of participants and personnel (performance bias)
All outcomes

High risk

Comment: No blinding.

Blinding of outcome assessment (detection bias)
All outcomes

Low risk

Comment: One independent therapist, who was not aware of any child's grouping or stage within the study, took all the measurements on gait parameters.

Incomplete outcome data (attrition bias)
Experimental group 1

Low risk

Regular therapeutic treatment

1. One child dropped out of the program before the third assessment. Reasons not reported.

Treadmill training

1. No dropouts.

Selective reporting (reporting bias)

High risk

Quote: "Outcomes measures included muscle tone..."

Comment: no data about muscle tone provided.

Other bias

Unclear risk

Comment: We did not have enough information to make a judgement.

Methods

Quasi‐randomised controlled trial.

Participants

Number randomised: 22 infants with Down syndrome randomised (10 intervention; 12 control). Number of males and females not reported.

Number analysed: 22 infants.

Dropouts/withdrawals: five infants discontinued the intervention in the control group.

Mean age (SD): 21.4 (4.0) months.

Ethnicity: not reported.

Interventions

Control group:

1. Treadmill training (5 days/week, 8 min/day), belt speed 0.2 m/s;

2. Co‐interventions of regular physical therapy.

Intervention:

1. Use of orthosis. Orthoses (SMOs): 8 hrs/wk, 5 days/wk, from entry to end of follow‐up;

2. Co‐interventions of treadmill training and regular physical therapy.Treadmill terminated at the onset of independent walking.

Outcomes

1. Average time in study until the infants achieved independent walking;

2. GMFM after one‐month follow‐up.

Notes

Country: USA.

Funding source: Funds provided by the Foundation for Physical Therapy PODS II awards to Dr Looper, a grant from the Michigan Physical Therapy Association, and a grant from the Rackham Graduate School, University of Michigan.

Risk of bias

Bias

Authors' judgement

Support for judgement

Random sequence generation (selection bias)

Unclear risk

Comment: The participants were randomly assigned to groups based on a random list of 1 (treadmill) and 2 (treadmill plus orthoses) from random.org. The first participant who entered the study (convenience sample) was assigned to the first number on the list, the second participant to the second number, the third to the third, etc.

Allocation concealment (selection bias)

Unclear risk

Comment: No information provided as regards how the allocation process took place.

Blinding of participants and personnel (performance bias)
All outcomes

High risk

Comment: Neither personnel nor participants were blinded.

Blinding of outcome assessment (detection bias)
All outcomes

High risk

Comment: No blinding.

Incomplete outcome data (attrition bias)
Experimental group 1

High risk

Orthosis and treadmill training:

1. 10 allocated;

2. All received the intervention and none discontinued the intervention;

3. 10 were analysed.

Treadmill training alone:

1. 12 allocated;

2. All received the intervention;

3. 5 discontinued intervention for the following reasons:

   1. 1 emerging medical problems;

   2. 1 did not tolerate the treadmill;

   3. 3 received orthoses prior to the end of the study.

4. 7 were analysed.

Selective reporting (reporting bias)

High risk

Comment: Anthropometric measurements were taken at each monthly visit, and treadmill training was videotaped. No information on either measurement or video assessment was reported. Also, age of onset of independent walking was not directly reported and the authors provided information about study duration only.

Other bias

Unclear risk

Comment: We did not have enough information to make a judgement.

Methods

Randomised controlled trial.

Participants

Number randomised: 24 infants with developmental delay met the inclusion criteria and were randomised (12 intervention; 12 control). Number of males and females not reported at this point.

Number analysed: 21 infants (12 intervention, 9 males and 3 females; 9 control, 8 males, 1 female).

Dropouts/withdrawals: three infants discontinued the intervention in the control group.

Mean age (SD): not reported; age ranged from 2 to 5 years (participants were aged 26 to 51 months in intervention group; participants were aged 27 to 48 months in control group).

Ethnicity: intervention group: 58.33% white, 25% black, 16.67% other; Control group: 90% white, 0% black, 10% other.

Interventions

Control:

1. All participants continued their physical therapy sessions consisting of therapeutic activities to promote functional stability and mobility, exercises focused on developing balance and coordination, and core and proximal strengthening activities.

Intervention:

1. Three additional body weight‐supported treadmill training (BWSTT) sessions of up to 15 minutes each per week, for 6 weeks.

2. The LiteGait gait training device placed over the Gait‐Keeper treadmill was used for all training sessions.

3. The BWSTT sessions took place at the participant's developmental preschool and were supervised by the primary investigators.

4. The participants began the study walking at speeds ranging from 0.54 to 0.80 m/s, treadmill inclination at a grade of 0 to 1, for 8 to 11.3 minutes.

5. Treadmill speed was increased within each session as tolerated, and subsequent sessions were initiated at the maximum speed achieved during the previous session.

6. As tolerated, body weight support was decreased with each participant achieving safe treadmill ambulation (with or without therapist facilitation).

Outcomes

1. 10‐minute walking test;

2. GMFM (dimensions D and E).

Notes

Country: USA.

Funding source: Grant support: NIGMS IDEA Program award P30 GM110702.

Risk of bias

Bias

Authors' judgement

Support for judgement

Random sequence generation (selection bias)

Low risk

Comment: Participants were randomised to the control or treatment group using a computer‐generated randomisation chart.

Allocation concealment (selection bias)

Unclear risk

Comment: No information provided.

Blinding of participants and personnel (performance bias)
All outcomes

High risk

Comment: No blinding.

Blinding of outcome assessment (detection bias)
All outcomes

Low risk

Comment: The testers established inter‐rater reliability: ICC more than 0.90 for each test.

Incomplete outcome data (attrition bias)
Experimental group 1

Low risk

Treadmill training:

1. 12 allocated;

2. All received the intervention and none discontinued the intervention

3. 12 were analysed, but 2 were excluded from specific analyses (1 gait velocity, because his baseline velocity was the mean gait velocity of his peers of his age without disability; 1 GMFM E, because the child's raw scores at baseline approached the maximum possible score, thus creating a ceiling effect).

Control:

1. 12 allocated;

2. All received the intervention;

3. 9 were analysed;

4. 1 excluded from specific analysis of GMFM D because the child's raw scores at baseline approached the maximum possible score, thus creating a ceiling effect;

5. Excluded from the analysis:

   1. 2 because of ceiling effect in all baseline analyses;

   2. 1 because of neurological referral during the study.

Selective reporting (reporting bias)

Low risk

Comment: no evidence of reporting bias.

Other bias

Unclear risk

Comment: none noted.

Methods

Controlled clinical trial.

Participants

Number randomised: 15 children with diagnosis of cerebral palsy (GMFCS levels I and II), who were able to sit for at least 30 seconds unsupported and demonstrated the ability to take 10 consecutive steps when held on hands or torso, were included. 12 children completed the study.

Number analysed: 12 children were quasi‐randomised and matched by GMFCS levels and age. 6 intervention (3 boys, 3 girls), 6 control (5 boys, 1 girl).

Dropouts/withdrawals: 3 (1 child became ill and had to be hospitalised, 1 child dropped out because family reasons, 1 child received genetic diagnosis therefore had to be excluded).

Mean age (SD): intervention 21.7 (6.5, range 15.5 to 32) months, control 21.3 (6.07, range 13.5 to 30.5) months.

Ethnicity: 2 African‐American, 2 Asian, 2 Hispanic, 6 white.

Interventions

Control:

1. All children received their weekly scheduled physical therapy sessions in their homes or at a physical therapy facility that excluded treadmill training.

Intervention

1. Treadmill training 6 times per week, twice daily for 10 to 20 minute sessions, for 6 weeks;

2. Children were encouraged to walk as many minutes as possible for each session. The time walked during each session was recorded on a flowchart by the parents.

Outcomes

1. GMFM (dimensions D and E);

2. PDMS‐2 (locomotion subscale);

3. 10‐minute walking test;

4. Functional Mobility Scale (FMS);

5. Frequence of alternating steps in 10 seconds (walking function);

6. Pediatric Evaulation of Disability Inventory (PEDI, mobility subscale).

Notes

Country: USA.

Funding source: Supported by a paediatric section research grant of the American Physical Therapy Association (grant number: 527109).

Risk of bias

Bias

Authors' judgement

Support for judgement

Random sequence generation (selection bias)

Unclear risk

Comment: Explained in CONSORT diagram, but no information in the text as regards how the randomisation took place.

Allocation concealment (selection bias)

Unclear risk

Comment: The children were quasi‐randomised by the principal investigators and matched by GMFCS levels and age.

Blinding of participants and personnel (performance bias)
All outcomes

High risk

Comment: No blinding. All participants aware of group allocation. No blinding of personnel, but blinding for some outcome measures.

Blinding of outcome assessment (detection bias)
All outcomes

Low risk

Comment: Blinding for the GMFM‐66 and PDMS‐2 was achieved by videotaping the children's gross motor skills in their homes. The videotapes were subsequently reviewed by a physical therapist who was blinded to group allocation.

Incomplete outcome data (attrition bias)
Experimental group 1

Low risk

Comment: All outcomes were reported.

Selective reporting (reporting bias)

Low risk

Comment: No evidence of reporting bias.

Other bias

Unclear risk

Comment: None noted.

Methods

Randomised controlled trial.

Participants

Number randomised: 32 infants with Down syndrome, randomised into 2 groups (16 intervention; 16 control); total number of males and females was not provided. Enrolled when able to sit for 30 seconds.

Number analysed: 30 (15 intervention (no breakdown by sex was provided for this group), 15 control (8 male, 7 female)).

Dropouts/withdrawals: 2 infants discontinued the intervention (one in each group) and 2 more were lost to gait follow‐up (one in each group), as reported in Wu 2007. Any discrepancies in the paper were resolved through oral discussion between MV and RA who was one of the authors involved in both this study and in Ulrich 2008, and who was also a review author.

Average age at entry: mean 10.1 months (SD 1.94).

Mean age (SD): control 10.2 (2.2) months, intervention 9.9 (1.7) months.

Ethnicity: 2 mixed race; remaining participants were white.

Interventions

Control:

1. Traditional physical therapy as well as any activity that was prescribed by their health care provider and early intervention team;

2. Researchers visited bi‐weekly to measure growth and assess child;

3. Parents kept a log book of the intervention and infant's response, which was shared with researcher.

Intervention:

1. Parents were trained in the treadmill intervention and delivered it 5 days/week; 8 min/session; belt speed 0.2 m/s;

2. It stopped when infants achieved independent walking (i.e. took 3 independent steps on the ground);

3. They also received traditional physical therapy as well as any activity that was prescribed by their health care provider and early intervention team.

Outcomes

1. Length of time from entry into study until the raising up to stand, the onset of walking with help or independent walking (i.e. taking 3 steps), which are items from the Bayley Scales of Infant Development.

Notes

Country: USA (Indiana, Tennesse, Ohio).

Funding sources: Grants from the National Institute for Disability and Rehabilitation Research and from the March of Dimes Birth Defects Foundation.

Other comments: The control group from this study was also used in another paper (Wu 2007) that relates to Ulrich 2008.

Risk of bias

Bias

Authors' judgement

Support for judgement

Random sequence generation (selection bias)

Low risk

Comment: Infants were randomised into two groups. In addition, Wu 2007 reported on the use of a table of random numbers

Allocation concealment (selection bias)

Unclear risk

Comment: We obtained the following information from another publication of the same study (Wu 2007):

Quote: "The randomisation procedure was conducted by the fourth investigator for the two cohorts separately via a table of random numbers".

Comment: This means that each randomisation was conducted separately with the involvement of only the 4th author and with the use of a table of random numbers. This does not give us enough information to make a judgement

Blinding of participants and personnel (performance bias)
All outcomes

High risk

Comment: Neither participants nor personnel were blinded. Infants in the treadmill intervention group had treadmills placed in their homes. Parents were trained to implement the training. A team of researchers visited all participants bi‐weekly throughout the study. Infants were videoed on the treadmill and their growth was assessed and parents maintained a log book that was read by a research staff member during each visit. Parents were asked to include information regarding the dates and length of their paediatric physical therapy sessions, the general activities that the therapist prescribed for parent implementation, and an estimate of the amount of time the parent spent implementing physical therapy activities at home.

Blinding of outcome assessment (detection bias)
All outcomes

High risk

Comment: Assessors were aware of infant's group assignment.

Incomplete outcome data (attrition bias)
Experimental group 1

Low risk

Comment: Treadmill training. One dropout was not reported in this paper but was reported in Wu 2007 (the same control group was used for this paper).

Selective reporting (reporting bias)

High risk

Comment: Not all outcomes were reported.

Other bias

Unclear risk

Comment: All parents were asked to keep a log book, including information regarding treadmill training (for those in the experimental group) and any other relevant information regarding the infant's health state and daily activities, including any therapeutic session administered other than treadmill training.

Quote: "Given that there were no group differences on the 11 anthropometric measures at entry, it appears that randomisation process resulted in producing comparable treatment groups".

Methods

Randomised controlled trial.

Participants

Number randomised: 36 infants with Down syndrome were randomised into two groups: low‐intensity (15 children) and high‐intensity (19 children). There were another two infants with unknown initial group allocation who withdrew from the study for emerging medical conditions. All participants were included when they were able to take 6 steps per minute on a treadmill while being supported.

Number analysed: 30 children were analysed in the final sample (16 high‐intensity training (12 males, 4 females), 14 low‐intensity training (6 males, 8 females); (28 with trisomy 21; two with mosaic type).

Dropouts/withdrawals: 6 infants discontinued the intervention (4 low‐intensity, 2 high‐intensity). An additional 5 infants were lost to gait follow‐up (2 low‐intensity, 3 high‐intensity). Any discrepancies in the paper were resolved through oral discussion between MV and RA who was one of the authors involved in both Ulrich 2001 and this study, and who was also a review author.

Corrected age at entry; mean (SD): higher‐intensity group 9.65 (1.61) months, lower‐intensity group 10.40 (2.14) months.

Ethnicity: 2 African American, 2 bi‐racial, and remaining infants were white.

Interventions

Control group (low‐intensity treadmill training):

1. 5 days/week, 6 min/session, belt speed 0.18 m/s;

2. Co‐interventions: early intervention services and any other activities that were prescribed by their health care providers;

3. The training stopped when infants could take 3 independent steps overground.

Experimental group (high‐intensity treadmill training):

1. 5 days/week, with two treadmill parameters (minutes/day, treadmill belt speed) individualised, as well as an ankle weight being added as the infant progressed in frequency of alternating steps;

2. Co‐interventions: early intervention services and any other activities that were prescribed by their health care providers.

Four additional publications (Wu 2007; Angulo‐Barroso 2008; Wu 2008; Wu 2010) dealt with the follow‐up from this intervention including assessments from 1 to 15 months postwalking onset (i.e. after termination of the intervention).

Outcomes

The study reported frequency of alternating treadmill steps and onset of assisted and independent walking. The follow‐up publications reported on spatio‐temporal variables, joint kinematics, and gait adaptation parameters. In addition, Wu 2007 presented follow‐up on spatio‐temporal gait variables, including a historical control group from Ulrich 2001 (we did not use these data as the study was not randomised).

Publication Wu 2007

1. Gait follow‐up assessment, between 1 and 3 months after walking onset (training groups), and 1 month after walking onset (control group);

2. Age at walking onset (decreased when any training, with further decreases in high‐intensity group = positive effects of training at higher intensities);

3. Elapsed time from entry to walking onset;

4. Gait speed;

5. Gait stride length;

6. Gait stride width.

Publication Angulo‐Barroso 2008

1. Measured after the onset of independent walking during 4 home visits scheduled at the following ages of the infants:

   1. Low‐intensity group: 24.9 (SD 5.1) months; 28.4 (SD 4.6) months; 30.5 (SD 5.1) months; 36.5 (SD 4.9) months;

   2. High‐intensity group: 21.3 (SD 2.4) months, 24.4 (SD 2.4) months, 27.3 (SD 2.3) months, 33.7 (SD 2.5) months;

   3. The walking experience prior to visit one had been 3.3 (SD 1.2) months for the low‐intensity group and 2.6 (SD 0.9) months for the high‐intensity group.

2. Velocity (increased after high‐intensity training = positive effect);

3. Cadence (increased after high‐intensity training = positive effect);

4. Step length (increased after high‐intensity training = positive effect);

5. Step width (decreased after high‐intensity training = positive effect);

6. Gait double‐limb support.

Publication Wu 2008

1. Age at onset of independent walking.

Publication Wu 2010

1. Toe‐off as % of gait cycle;

2. Joint angle (ankle: plantar flexion and dorsiflexion; hip: extension and flexion and abduction and adduction; knee: extension and flexion).

Notes

Country: USA (Michigan, Ohio, Indiana).

Funding sources: Research grant from the US Office of Special Education and Rehabilitative Services (H324C010067), a US Office of Special Education Programs Leadership Training Grant (H325D020028), and the Steelcase Foundation in Michigan.

Risk of bias

Bias

Authors' judgement

Support for judgement

Random sequence generation (selection bias)

Low risk

Comment: Used a random numbers table to assign to either low‐intensity training group or high‐intensity training group (described in Wu 2007).

Allocation concealment (selection bias)

Unclear risk

Comment: We obtained the following information from another publication of the same study (Wu 2007):

Quote: "The randomisation procedure was conducted by the fourth investigator for the two cohorts separately via a table of random numbers."

Comment: This means that each randomisation was conducted separately with the involvement of only the 4th author and with the use of a table of random numbers. This did not give us enough information to make a judgement.

Blinding of participants and personnel (performance bias)
All outcomes

High risk

Comment: No blinding of participants or personnel.

Blinding of outcome assessment (detection bias)
All outcomes

High risk

Comment: No blinding of outcome assessment.

Incomplete outcome data (attrition bias)
Experimental group 1

Low risk

High‐intensity treadmill training:

1. 20 allocated;

2. 3 excluded from the analyses because their parents did not routinely adhere to the protocol;

3. 1 also excluded from the analysis because of emerging medical conditions.

Low‐intensity treadmill training:

1. 16 allocated;

2. 1 excluded from the analyses because their parents did not routinely adhere to the protocol;

3. 1 also excluded from the analysis because of emerging medical conditions.

Selective reporting (reporting bias)

Unclear risk

Comment: It is not clear if all data are reported.

Other bias

Unclear risk

Comment: We did not have enough information to make a judgement.