2.1.7 Blinding - Revision history

ChristophEmmerich at 19:43, 23 March 2021

2021-03-23T19:43:56Z

← Older revision		Revision as of 19:43, 23 March 2021
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	EQIPD expects that the method(s) used to implement blinding are described in as much detail as possible:		EQIPD expects that the method(s) used to implement blinding are described in as much detail as possible:
	* either as a dedicated protocol (please see below for a template that may serve as an example of how to build such a protocol),		* either as a dedicated protocol (please see below for a template that may serve as an example of how to build such a protocol),
	* or as a separate section of a study ~~plan~~.		* or as a separate section of a study protocol.

	Depending on the breadth of research methods in use, a given research unit may have one or more blinding protocols that can support blinding for specific types of experiments.		Depending on the breadth of research methods in use, a given research unit may have one or more blinding protocols that can support blinding for specific types of experiments.

ChristophEmmerich at 10:26, 15 February 2021

2021-02-15T10:26:52Z

← Older revision		Revision as of 10:26, 15 February 2021
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	In all cases, however, full and transparent reporting of how blinding was applied is expected.		In all cases, however, full and transparent reporting of how blinding was applied is expected.


	== B. Guidance & Expectations ==		== B. Guidance & Expectations ==

imported>Isabel A. Lefevre: Details added to sentence defining blinding

2021-01-29T11:36:10Z

Details added to sentence defining blinding

← Older revision		Revision as of 11:36, 29 January 2021
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	'''Blinding''' refers to the masking of the treatment, prior intervention ~~or condition~~ for the person(s) performing the experiment, collecting data and assessing outcome. Blinding aims to make sure that each person involved has no information on the experimental units (animals, subjects or samples) in each experimental group that could systematically influence his/her performance. The intended result is that (as far as possible) all experimental units in the experiment are dealt with equally.		'''Blinding''' refers to the masking of the treatment, physiological or pathological condition, genotype or any prior intervention for the person(s) performing the experiment, collecting data and assessing outcome. Blinding aims to make sure that each person involved has no information on the experimental units (animals, subjects or samples) in each experimental group that could systematically influence his/her performance. The intended result is that (as far as possible) all experimental units in the experiment are dealt with equally.

	In the discussion below, experimental groups refers to '''all''' groups within an experiment, for example: control, sham, treated with drug A, treated with drug B, etc.		In the discussion below, experimental groups refers to '''all''' groups within an experiment, for example: control, sham, treated with drug A, treated with drug B, etc.
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	The group allocation, actions and outcome assessments are ‘'''blinded'''’. People are ‘'''blind'''’ to particular information.		The group allocation, actions and outcome assessments are ‘'''blinded'''’. People are ‘'''blind'''’ to particular information.

	Blinding requires at least 2 people, one blinded person (unaware of experimental condition) and ~~an unblinded~~ person (knows the experimental condition and the blinding code). The ~~unblinded~~ person is the keeper of the blinding code, which needs to be concealed until all processes under blinding are concluded.		Blinding requires at least 2 people, one blinded person (unaware of experimental condition) and a non-blinded person (knows the experimental condition and the blinding code). The non-blinded person is the keeper of the blinding code, which needs to be concealed until all processes under blinding are concluded.

	The most effective blinding covers every step in an experiment - from allocation to treatment conditions, application of treatment to data collection and analysis - this is often referred to as '''full blinding'''.		The most effective blinding covers every step in an experiment - from allocation to treatment conditions, application of treatment to data collection and analysis - this is often referred to as '''full blinding'''.

imported>Isabel A. Lefevre: Mainly English language and typo edits, a few additional details

2021-01-26T19:11:18Z

Mainly English language and typo edits, a few additional details

← Older revision		Revision as of 19:11, 26 January 2021
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	'''Blinding''' refers to the masking of the treatment ~~allocation~~ for person(s) ~~who perform~~ the experiment, ~~collect~~ data and ~~assess~~ outcome. Blinding aims to make sure that each person involved has no ~~knowledge about treatment allocation~~ that could systematically influence his/her performance. The intended result is ~~the equal treatment~~ (as far as possible) of all experimental units ~~(animals, subjects or samples)~~ in the experiment.		'''Blinding''' refers to the masking of the treatment, prior intervention or condition for the person(s) performing the experiment, collecting data and assessing outcome. Blinding aims to make sure that each person involved has no information on the experimental units (animals, subjects or samples) in each experimental group that could systematically influence his/her performance. The intended result is that (as far as possible) all experimental units in the experiment are dealt with equally.

	In the discussion below, experimental groups refers to '''all''' groups within an experiment, for example: control, sham, treated with drug A, treated with drug B, etc.		In the discussion below, experimental groups refers to '''all''' groups within an experiment, for example: control, sham, treated with drug A, treated with drug B, etc.

165.225.77.35: Mainly English language and typo edits, a few additional details

2021-01-26T16:45:34Z

Mainly English language and typo edits, a few additional details

85.216.81.116: /* B. Guidance & Expectations */

2021-01-11T17:40:02Z

B. Guidance & Expectations

← Older revision		Revision as of 17:40, 11 January 2021
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	* "Who does what?"		* "Who does what?"
	** сlearly define the roles for those involved in the experiment and the blinding procedure (e.g., see section 4 in the blinding protocol ~~template below~~);		** сlearly define the roles for those involved in the experiment and the blinding procedure (e.g., see section 4 in the [https://paasp.sharepoint.com/:w:/s/EQIPD/EZbRvZmZGoRGtsjc1Wk_XOsBLsnNAbg-FBFVj9h199oYMA?e=vIXtkO blinding protocol]);
	** the blinding protocol should make clear who is aware of the group allocation at the different stages of the experiment (during the allocation, the conduct of the experiment, the outcome assessment, and the data analysis);		** the blinding protocol should make clear who is aware of the group allocation at the different stages of the experiment (during the allocation, the conduct of the experiment, the outcome assessment, and the data analysis);
	** to effectively blind a study, create a sequence containing all experimental steps of the study and, for each step, indicate the name of each person involved in the conduct and analysis of the study. For each experimental step, document for each person whether they are blinded or not blinded to the condition. Such an overview systematically creates a transparent workflow of blinded and unblinded personnel and shows when unintended unblinding might occur. Such overview (e.g. as a table) can be made part of experimental documentation and reporting.		** to effectively blind a study, create a sequence containing all experimental steps of the study and, for each step, indicate the name of each person involved in the conduct and analysis of the study. For each experimental step, document for each person whether they are blinded or not blinded to the condition. Such an overview systematically creates a transparent workflow of blinded and unblinded personnel and shows when unintended unblinding might occur. Such overview (e.g. as a table) can be made part of experimental documentation and reporting.

85.216.81.116: /* C. Resources */

2021-01-11T17:39:07Z

C. Resources

← Older revision		Revision as of 17:39, 11 January 2021
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	Template to develop a written description of the method used to implement blinding:		Template to develop a written description of the method used to implement blinding:
	* [[https://paasp.sharepoint.com/:w:/s/EQIPD/EZbRvZmZGoRGtsjc1Wk_XOsBLsnNAbg-FBFVj9h199oYMA?e=vIXtkO blinding protocol]]		* [https://paasp.sharepoint.com/:w:/s/EQIPD/EZbRvZmZGoRGtsjc1Wk_XOsBLsnNAbg-FBFVj9h199oYMA?e=vIXtkO blinding protocol]

	Reading material:		Reading material:

85.216.81.116: /* C. Resources */

2021-01-11T17:38:49Z

C. Resources

← Older revision		Revision as of 17:38, 11 January 2021
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	Template to develop a written description of the method used to implement blinding:		Template to develop a written description of the method used to implement blinding:
	* [blinding protocol]		* [[https://paasp.sharepoint.com/:w:/s/EQIPD/EZbRvZmZGoRGtsjc1Wk_XOsBLsnNAbg-FBFVj9h199oYMA?e=vIXtkO blinding protocol]]

	Reading material:		Reading material:

85.216.81.116: /* B. Guidance & Expectations */

2021-01-11T17:04:29Z

B. Guidance & Expectations

← Older revision		Revision as of 17:04, 11 January 2021
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	* "Who does what?"		* "Who does what?"
	** for those involved in the experiment and the blinding procedure~~, are the roles clearly defined?~~ (e.g. see section 4 in the blinding protocol template below);		** сlearly define the roles for those involved in the experiment and the blinding procedure (e.g., see section 4 in the blinding protocol template below);
	** ~~from~~ the blinding protocol~~, it~~ should be clear who is aware of the group allocation at the different stages of the experiment (during the allocation, the conduct of the experiment, the outcome assessment, and the data analysis);		** the blinding protocol should make clear who is aware of the group allocation at the different stages of the experiment (during the allocation, the conduct of the experiment, the outcome assessment, and the data analysis);
	** to effectively blind a study, create a sequence containing all experimental steps of the study and, for each step, indicate the name of each person involved in the conduct and analysis of the study. For each experimental step, document for each person whether they are blinded or not blinded to the condition ~~or not involved at all~~. Such an overview systematically creates a transparent workflow of blinded and unblinded personnel and shows when unintended unblinding might occur. Such overview (e.g. as a table) can be made part of experimental documentation and reporting.		** to effectively blind a study, create a sequence containing all experimental steps of the study and, for each step, indicate the name of each person involved in the conduct and analysis of the study. For each experimental step, document for each person whether they are blinded or not blinded to the condition. Such an overview systematically creates a transparent workflow of blinded and unblinded personnel and shows when unintended unblinding might occur. Such overview (e.g. as a table) can be made part of experimental documentation and reporting.
	** it is generally expected and strongly recommended that any process using humans as perceptors, raters or interpreters needs to be blinded until the decision-making is concluded.		** it is generally expected and strongly recommended that any process using humans as perceptors, raters or interpreters needs to be blinded until the decision-making is concluded.

	* Blinding code		* Blinding code
	** how is the blinding code developed and which specific steps are taken to practically apply it?		** describe how the blinding code is developed and which specific steps are taken to practically apply it?
	** one simple blinding strategy is to assign each subject / sample a separate number of letter (or a combination thereof). This approach may create compliance issues in case of a large number of subjects / samples and the need to apply treatment repeatedly over extended periods of time.		** one simple blinding strategy is to assign each subject / sample a separate number of letter (or a combination thereof). This approach may create compliance issues in case of a large number of subjects / samples and the need to apply treatment repeatedly over extended periods of time.
	** another blinding strategy is to assign each experimental group a separate number of letter (or a combination thereof). This approach may be problematic when human processing and rating is involved in outcome assessment. The assessor may not know the condition behind the code but the knowledge of a group affiliation of a sample can influence rating.		** another blinding strategy is to assign each experimental group a separate number of letter (or a combination thereof). This approach may be problematic when human processing and rating is involved in outcome assessment. The assessor may not know the condition behind the code but the knowledge of a group affiliation of a sample can influence rating.

Anton.bespalov at 14:19, 22 December 2020

2020-12-22T14:19:47Z

← Older revision		Revision as of 14:19, 22 December 2020
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	~~THIS ITEM IS UNDER CONSTRUCTION~~

	~~~~


	== A. Background & Definitions ==		== A. Background & Definitions ==

← Older revision		Revision as of 16:45, 26 January 2021
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	'''Blinding''' refers to the masking of the treatment allocation for person(s) who perform the experiment, collect data and assess outcome. Blinding aims to make sure that ~~someone~~ has no knowledge about treatment allocation that ~~may~~ systematically influence his/her performance. The intended result is the equal treatment (as far as possible) of all experimental units (animals, subjects or samples) in the experiment.		'''Blinding''' refers to the masking of the treatment allocation for person(s) who perform the experiment, collect data and assess outcome. Blinding aims to make sure that each person involved has no knowledge about treatment allocation that could systematically influence his/her performance. The intended result is the equal treatment (as far as possible) of all experimental units (animals, subjects or samples) in the experiment.

	In the discussion below, experimental groups ~~refer~~ to '''all''' groups ~~involved in~~ an experiment, for example: control, sham, treated with drug A, treated with drug B, etc.		In the discussion below, experimental groups refers to '''all''' groups within an experiment, for example: control, sham, treated with drug A, treated with drug B, etc.

	Group allocation describes which experimental unit (animal, subject or sample) has been allocated to which experimental group.		Group allocation describes which experimental unit (animal, subject or sample) has been allocated to which experimental group.
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	The group allocation, actions and outcome assessments are ‘'''blinded'''’. People are ‘'''blind'''’ to particular information.		The group allocation, actions and outcome assessments are ‘'''blinded'''’. People are ‘'''blind'''’ to particular information.

	Blinding requires at least 2 people, one blinded person (unaware of experimental condition) and an unblinded person (knows the experimental condition and the blinding code). The unblinded person is the keeper of the blinding code which needs to be concealed until all processes under blinding are concluded.		Blinding requires at least 2 people, one blinded person (unaware of experimental condition) and an unblinded person (knows the experimental condition and the blinding code). The unblinded person is the keeper of the blinding code, which needs to be concealed until all processes under blinding are concluded.

	The most effective blinding covers every step in an experiment - from allocation to treatment conditions, application of treatment to data collection and analysis - this is often referred to as '''full blinding'''.		The most effective blinding covers every step in an experiment - from allocation to treatment conditions, application of treatment to data collection and analysis - this is often referred to as '''full blinding'''.

	Blinding should '''not''' be seen as "all or none". There are several situations ~~when~~ partial blinding may be applied (i.e. blinding of the most risk-prone step(s) in the experimental process). For example, partial blinding can be considered when:		Blinding should '''not''' be seen as "all or none". There are several situations in which partial blinding may be applied (i.e., blinding of the most risk-prone step(s) in the experimental process). For example, partial blinding can be considered when:
	* a research unit with no prior experience with blinding is introducing a blinding procedure and, for organizational or other reasons, follows a ~~stepwise~~ implementation		* a research unit with no prior experience with blinding is introducing a blinding procedure and, for organizational or other reasons, follows a step-wise implementation
	* a research unit has significantly constrained human resources and does not intend to conduct knowledge-claiming research		* a research unit has significantly constrained human resources and does not intend to conduct knowledge-claiming research

	In ~~any case~~, full and transparent reporting of how blinding was applied is expected.		In all cases, however, full and transparent reporting of how blinding was applied is expected.

	== B. Guidance & Expectations ==		== B. Guidance & Expectations ==


	EQIPD expects that the method(s) to implement blinding are described ~~with~~ as much ~~details~~ as possible:		EQIPD expects that the method(s) used to implement blinding are described in as much detail as possible:
	* either as a dedicated protocol (please see below for a template that may serve as an example on how to build such a protocol),		* either as a dedicated protocol (please see below for a template that may serve as an example of how to build such a protocol),
	* or as a separate section of a study plan.		* or as a separate section of a study plan.

	~~Dependent~~ on the breadth of research methods in use, a given research unit may have one or more blinding protocols that can support blinding for specific types of experiments.		Depending on the breadth of research methods in use, a given research unit may have one or more blinding protocols that can support blinding for specific types of experiments.

	When preparing a blinding protocol, the main objective is to have a description that is understandable for the actual users - i.e. bench scientists (especially, those that are new to the unit). Therefore, it should be written in a simple language with as many examples (specific to the research) as appropriate.		When preparing a blinding protocol, the main objective is to have a description that is understandable for the actual users - i.e., bench scientists (especially those that are new to the unit). Therefore, it should be written in a simple language with as many examples (specific to the research) as appropriate.

	A blinding protocol may describe the following:		A blinding protocol may describe the following:
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	** сlearly define the roles for those involved in the experiment and the blinding procedure (e.g., see section 4 in the [https://paasp.sharepoint.com/:w:/s/EQIPD/EZbRvZmZGoRGtsjc1Wk_XOsBLsnNAbg-FBFVj9h199oYMA?e=vIXtkO blinding protocol]);		** сlearly define the roles for those involved in the experiment and the blinding procedure (e.g., see section 4 in the [https://paasp.sharepoint.com/:w:/s/EQIPD/EZbRvZmZGoRGtsjc1Wk_XOsBLsnNAbg-FBFVj9h199oYMA?e=vIXtkO blinding protocol]);
	** the blinding protocol should make clear who is aware of the group allocation at the different stages of the experiment (during the allocation, the conduct of the experiment, the outcome assessment, and the data analysis);		** the blinding protocol should make clear who is aware of the group allocation at the different stages of the experiment (during the allocation, the conduct of the experiment, the outcome assessment, and the data analysis);
	** to effectively blind a study, create a sequence containing all experimental steps of the study and, for each step, indicate the name of each person involved in the conduct and analysis of the study. For each experimental step, document for each person whether they are blinded or not blinded to the condition. Such an overview systematically creates a transparent workflow of blinded and unblinded personnel and shows ~~when~~ unintended unblinding might occur. Such overview (e.g. as a table) can be made part of experimental documentation and reporting.		** to effectively blind a study, create a sequence containing all experimental steps of the study and, for each step, indicate the name of each person involved in the conduct and analysis of the study. For each experimental step, document for each person whether they are blinded or not blinded to the condition. Such an overview systematically creates a transparent workflow of blinded and unblinded personnel and shows at which step unintended unblinding might occur. Such an overview (e.g., as a table) can be made part of the experimental documentation and reporting.
	** it is generally expected and strongly recommended that any process using humans as perceptors, raters or interpreters needs to be blinded until the decision-making is concluded.		** it is generally expected and strongly recommended that any process using humans as perceptors, raters or interpreters needs to be blinded until the decision-making is concluded.

	* Blinding code		* Blinding code
	** describe how the blinding code is developed and which specific steps are taken to practically apply it?		** describe how the blinding code is developed and which specific steps are taken to practically apply it
	** one simple blinding strategy is to assign each subject / sample a separate number of letter (or a combination thereof). This approach may create compliance issues ~~in case of a~~ large ~~number~~ of subjects / samples and the need to ~~apply~~ treatment repeatedly over extended periods of time.		** one simple blinding strategy is to assign each subject / sample a separate number or letter (or a combination thereof). This approach may create compliance issues with large numbers of subjects / samples and the need to administer treatment repeatedly over extended periods of time.
	** another blinding strategy is to assign each experimental group a separate number of letter (or a combination thereof). This approach may be problematic when human processing and rating is involved in outcome assessment. The assessor may not know the condition behind the code but the knowledge of a group affiliation of a sample can influence rating.		** another blinding strategy is to assign each experimental group a separate number or letter (or a combination thereof). This approach may be problematic when human processing and rating is involved in outcome assessment. The assessor may not know the condition behind the code but the knowledge of a group affiliation of a sample can influence rating.
	** the decision which strategy to follow is made by the researchers taking into account the ~~details of a specific experiment~~ and associated risks.		** the decision of which strategy to follow is made by the researchers, taking into account the specifics and associated risks for each experiment.


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	* Generation of alphanumeric codes for blinding		* Generation of alphanumeric codes for blinding
	** if possible, ~~check whether it is possible to~~ use a blinding ~~scheme without~~ repeating codes. This can be easily done with alphanumeric code consisting of 4 letter/number combinations, such as T7Z4. Such codes can be generated in Excel using the following formula:		** if possible, use blinding schemes with no repeating codes. This can be easily done with an alphanumeric code consisting of 4 letter/number combinations, such as T7Z4. Such codes can be generated in Excel using the following formula:
	*** =CHAR(RANDBETWEEN(65;))&RANDBETWEEN(0;9)&CHAR(RANDBETWEEN(65;))&RANDBETWEEN(0;9)		*** =CHAR(RANDBETWEEN(65;))&RANDBETWEEN(0;9)&CHAR(RANDBETWEEN(65;))&RANDBETWEEN(0;9)
	*** enter this formula in a row of cells for which you need coded samples and copy the outcome to another worksheet with the command Past Special-->Paste Values.		*** enter this formula in a row of cells for which you need coded samples and copy the outcome to another worksheet with the command Past Special-->Paste Values.

	* Allocation concealment in animal experiments		* Allocation concealment in animal experiments
	** to ~~prevents~~ selection bias, the investigator shall not be aware and/or have the choice to which treatment group an animal is allocated to;		** to prevent selection bias, the investigator shall not be aware and/or have the choice of which treatment group an animal is allocated to;
	** therefore, the assignment to a specific group needs to be concealed and every animal should have the same chance to be assigned to each of the groups;		** therefore, the assignment to a specific group needs to be concealed and every animal should have the same chance to be assigned to each of the groups;
	** this can be achieved by separating the assignment of animal_IDs to each animal (e.g. individual ear mark or subcutaneous chip) and randomization of treatments (see randomization) into two independent processes and then merging the two.		** this can be achieved by separating the assignment of animal_IDs to each animal (e.g., individual ear mark or subcutaneous chip) and randomization of treatments (see randomization) into two independent processes and then merging the two.


	'''RISK ASSESSMENT'''		'''RISK ASSESSMENT'''
	* Under some circumstances, unintentional unblinding (e.g. due to a ~~different~~ appearance of a positive control in solution or suspension) may be a risk to be assessed and/or controlled		* Under some circumstances, unintentional unblinding (e.g., due to a difference in appearance of a positive control in solution or suspension) may be a risk to be assessed and/or controlled
	* Experimental treatments may produce adverse effects and attending veterinarians and animal care stuff may need to be informed in advance ~~about~~ the possibility of such adverse effects occurring and, if necessary, have emergency access to the blinding protocol.		* Experimental treatments may produce adverse effects and attending veterinarians and animal care stuff may need to be informed in advance of the possibility of such adverse effects occurring and, if necessary, have emergency access to the blinding protocol.
	* if a blinding code is added to another code such as animal_ID, measurement_ID or file name, watch out for hidden cues in such IDs, containing temporal or sequential information that could increase rater bias. Also metadata, such as creation date and time of a file ~~containg~~ measurements can give away experimental conditions.		* if a blinding code is added to another code such as animal_ID, measurement_ID or file name, watch out for hidden cues in such IDs, containing temporal or sequential information that could increase rater bias. Also metadata, such as creation date and time of a file containing measurements can give away experimental conditions.


	'''PLEASE DO NOT FORGET'''		'''PLEASE DO NOT FORGET'''

	* Blinding is sometimes not possible especially when certain cues cannot be blinded, such as skin color of transgenic mice or color of a solution in a well. It is important to document this and to communicate in reports where blinding could or could not be achieved.		* Blinding is sometimes not possible especially when certain cues cannot be blinded, such as skin color or weight/size of transgenic mice or color of a solution in a well. It is important to document this and to communicate in reports where blinding could or could not be achieved.
	* Unblinding of the experimental conditions should be done when all blinded processes for the entire study are concluded. Early and partial unblinding for "checking" should be avoided and, if necessary, be part of the study protocol.		* Unblinding of the experimental conditions should be done when all blinded processes for the entire study are concluded. Early and partial unblinding for "checking" should be avoided and, if necessary, be part of the study protocol.
	* Control group(s) (e.g., positive control group) should not be excluded from the blinding procedure.		* Control group(s) (e.g., positive control group) should not be excluded from the blinding procedure.

2.1.7 Blinding - Revision history

ChristophEmmerich at 19:43, 23 March 2021

ChristophEmmerich at 10:26, 15 February 2021

imported>Isabel A. Lefevre: Details added to sentence defining blinding

imported>Isabel A. Lefevre: Mainly English language and typo edits, a few additional details

165.225.77.35: Mainly English language and typo edits, a few additional details

85.216.81.116: /* ​B. Guidance & Expectations */

85.216.81.116: /* C. Resources​ */

85.216.81.116: /* C. Resources​ */

85.216.81.116: /* ​B. Guidance & Expectations */

Anton.bespalov at 14:19, 22 December 2020

85.216.81.116: /* B. Guidance & Expectations */

85.216.81.116: /* C. Resources */

85.216.81.116: /* C. Resources */

85.216.81.116: /* B. Guidance & Expectations */