Can the IOS Scale Show Whether Closeness Is Mutual?

What the circles actually ask one person to report

One IOS answer reports how much one respondent experiences another person as included in their sense of self. It is that person’s account of closeness, not a guess at what their partner feels. The seven pairs of circles overlap a little more with each choice. The respondent selects the pair that best describes their relationship with a specific person. The picture is simple; the experience behind it may not be.

As the article “Measuring the Closeness of Relationships: A Comprehensive Evaluation of the ‘Inclusion of the Other in the Self’ Scale” explains, the IOS asks one person to describe their own relationship with “X.” Its answer is deliberately neutral about why that person feels close or distant. Emotional intimacy, shared history, longing, spiritual recognition, or a sense of interdependence may all shape the choice. The circles do not sort those reasons. They give one person a compact way to represent a felt degree of connection.

That breadth is part of the scale’s usefulness. In three online studies involving 772 adults in the United States, the evaluation found IOS responses positively correlated with six other measures designed to capture relationship closeness. The authors concluded that IOS is a psychologically meaningful and reliable measure of subjective closeness. The result supports taking a person’s choice seriously as a report of their experience. It does not make the answer a complete account of the relationship.

The literature review “Pair-Bonding as Inclusion of Other in the Self” describes the circles as a metaphor for overlapping selves: in close relationships, people may experience a partner’s perspectives, resources, and identity as partly their own. That helps explain why the image can feel apt when someone experiences a strong “we.” Yet the scale still asks for one selection from one respondent. It does not reveal which moments created that feeling, whether the partner experiences the same overlap, or what either person wants next.

So a high-overlap choice can name something meaningful: this person feels deeply connected. It cannot answer for the partner, or by itself establish reciprocal care and choice. Keep the experience; leave the verdict open. To understand mutuality, the other person’s own account has to enter the conversation.

Sources: Measuring the Closeness of Relationships: A Comprehensive Evaluation of the ‘Inclusion of the Other in the Self’ Scale; Pair-Bonding as Inclusion of Other in the Self

Why felt overlap and shared participation are different questions

The circles can make a private feeling visible. They cannot show who carries the relationship. The Inclusion of the Other in the Self Scale asks one person to choose which of seven pairs of circles best represents their relationship with someone else. More overlap means the respondent feels the other person is more included in their own world. But it records a perception, not a history of what both people have done. The self-expansion account helps explain why the image can feel apt. In “Eliciting Short-Term Closeness in Couple Relationships With Ecological Momentary Interventions,” closeness is described as including another person’s resources, perspectives, and identity in one’s sense of self. Your partner’s hopes may matter to you, their perspective may change your own, and you may think in terms of “we.” That overlap says something real about how the connection lives in you. Yet a felt “we” and a shared pattern of action are related questions, not identical ones. The same paper describes cognitive, emotional, physical, and behavioral dimensions of closeness. It notes that evidence for the IOS capturing behavioral interdependence, such as how partners’ activities depend on one another, is mixed. Its clearest reading is broader: the scale measures subjectively experienced closeness. “Measuring the Closeness of Relationships: A Comprehensive Evaluation of the ‘Inclusion of the Other in the Self’ Scale” likewise treats IOS as one respondent’s report and tests its relationship to other closeness measures. Neither finding turns the circles into a record of who initiates, listens, compromises, or returns to repair. Consider an example. After several intimate conversations, one partner chooses the circles with deep overlap. They feel understood; the other person’s inner life has become important to them. That choice deserves respect. It captures an experience, not an illusion. Still, it leaves open what happens when plans conflict, one person asks for support, or an apology is needed. Does each partner make room for the other? Can both name a need without pressure? Do they find their way back after a hurt? Those questions give closeness a shared-life context. A strong sense of recognition may be part of why a bond feels spiritually meaningful, but the IOS cannot tell you whether the other person feels the same recognition or participates in the same way. That answer has to come from their own words and choices. Let the overlap mean what it can: one person’s felt closeness. Then ask what both people build around it. To compare two people’s perceptions, each must answer for themselves.

Sources: Eliciting Short-Term Closeness in Couple Relationships With Ecological Momentary Interventions; Measuring the Closeness of Relationships: A Comprehensive Evaluation of the ‘Inclusion of the Other in the Self’ Scale

Can two IOS answers show whether partners feel equally close?

Yes, two IOS answers can show whether partners report similar levels of closeness, provided each person answers independently about the same partner. It is not a direct measure of mutuality. Matching circles don't prove that both people give, receive, or choose closeness in the same way; different circles don't tell you why their experiences differ. The scale asks one respondent to select the pair of circles that best describes their relationship with a person. In “Measuring the Closeness of Relationships: A Comprehensive Evaluation of the ‘Inclusion of the Other in the Self’ Scale,” three online studies with 772 US adults found that IOS responses correlated with six other measures designed to capture relationship closeness. The task still asks each person to speak for themselves. For a fair comparison, each partner should choose privately before seeing the other's answer. They should have the same person in mind and answer with a similar time frame: how the relationship feels lately, rather than one person thinking about the first months together and the other thinking about this week. Neither should try to produce a matching pair. Then read the answers as ordered pictures, not as marks on a calibrated ruler. The seven pairs show increasing overlap, but the scale does not give a universal rule for what a one-step gap means, whether a larger gap is serious, or which partner is “right.” A difference shows that two people chose different pictures. Nor does agreement prove that either person has accurately guessed the other's inner life. Imagine both choose a pair with little overlap. That could mean each is content with a quieter or more separate bond. It could also mean both feel distant and wish things were closer. The matching answer alone cannot distinguish those readings. If both choose near-total overlap, the same limit applies: one may feel cherished and understood, while the other may be describing a strong sense of shared identity or history. Similar answers can carry different meanings. Now imagine one partner chooses much more overlap than the other. Research makes this distinction especially useful. “The Complicated Connection Between Closeness and the Quality of Romantic Relationships,” a study of 103 cohabiting US couples, examined partners' actual-closeness differences separately from each person's difference between actual and ideal closeness. In its model, the partner-to-partner difference itself was not associated with relationship quality, while actual-to-ideal discrepancies were associated with poorer quality for both people. The sample and observational design limit what can be concluded, and the finding doesn't erase any couple's pain. It does show why a gap between answers cannot carry the whole interpretation. So compare the pictures, then ask what each one means. “What did you have in mind when you chose that pair? Does this feel like the amount of closeness you want?” The two selections can locate a question worth asking. Only the partners can explain their meaning.

Sources: Measuring the Closeness of Relationships: A Comprehensive Evaluation of the ‘Inclusion of the Other in the Self’ Scale; The Complicated Connection Between Closeness and the Quality of Romantic Relationships

The crucial comparison: between partners or within each person?

A difference between two partners’ current IOS answers and a difference between one person’s current and desired closeness are separate comparisons. The first asks whether their reports match. The second asks whether each person feels as close as they want to feel. Those questions can lead to different readings, so the numbers shouldn’t be collapsed into one verdict about mutuality.

In The Complicated Connection Between Closeness and the Quality of Romantic Relationships, the researchers measured both kinds of difference. Each person chose circles for actual closeness and again for ideal closeness. They compared Partner A’s actual answer with Partner B’s, then each person’s actual answer with their own ideal. In everyday terms: “How close do we each feel?” is not the same as “Does each of us feel close enough?”

Imagine one couple in which one partner chooses a little more overlap than the other. Each, when asked about their ideal, says their present closeness feels right. Now imagine another couple whose partners choose matching circles, yet one says the current amount falls well short of what they want. In the first pair, the answers differ while both people feel met. In the second, the answers match while one person feels a meaningful gap. These imagined examples illustrate the distinction; they aren’t study participants or outcomes.

The study examined 103 cohabiting couples in the United States, or 206 people. Each partner completed the questionnaire on their own. Using an actor-partner analysis, the researchers examined how one person’s closeness experience related to their own and their partner’s relationship quality, accounting for the fact that they belonged to the same couple. Each person’s mismatch between actual and ideal closeness was associated with poorer relationship quality for both partners. By contrast, differences between partners’ actual answers were not meaningfully associated with relationship quality in the model. This is an association, not proof that a mismatch causes distress or that partners’ differences never matter.

That result shifts the useful follow-up. It doesn’t say to ignore a painful difference, or that desired closeness is all that matters. The sample involved cohabiting US couples, mostly married or in civil unions or domestic partnerships. Other relationships may not fit the same pattern, and an average result can’t overrule one person’s experience. The study also offers no universal cutoff for how much difference is healthy for every couple.

So ask both questions: “What circles describe your closeness right now?” Then, “Is that the amount of closeness you want?” Similar choices don’t establish equal investment, and different choices don’t establish unequal love. Hearing what each person wants gives the gap context: whether it feels comfortable or painful. That’s a clearer starting point than the distance between two circle choices alone.

Sources: The Complicated Connection Between Closeness and the Quality of Romantic Relationships; Closeness Discrepancies in Romantic Relationships

Why the amount of closeness someone wants matters

More closeness is not automatically better for every person. What matters is whether that amount fits what they want.A partner may choose fewer overlapping circles and feel content. Another may choose the same picture yet feel lonely because the relationship falls short. Equal answers and equal satisfaction are different things.

The 2022 study “The Complicated Connection Between Closeness and the Quality of Romantic Relationships” examined 103 cohabiting US couples. Each partner reported current and ideal closeness. A dyadic model related each person’s answers to both partners’ relationship quality. A person’s mismatch between actual and ideal closeness was associated with poorer quality for both partners. This association remained after accounting for actual closeness and differences between partners. In this sample, the within-person mismatch carried information that the gap between partners’ current answers alone did not.

That result complicates the tempting rule that a couple should want the same amount of togetherness. Imagine one partner wants frequent shared time while the other prefers room for separate pursuits. If both feel their rhythm is respected, different answers need not mean either feels deprived. Now imagine two partners choosing the same circles, while one wishes for more conversation or time together. Their match hides an unmet desire. These are illustrations, not cases reported by the study.

A separate longitudinal study, “Closeness Discrepancies in Romantic Relationships,” followed partnered individuals over two years. Its abstract reports that well-being was highest when actual IOS closeness sat near a person’s ideal, regardless of actual level. Participants whose actual closeness moved nearer their ideal also reported improved relational well-being and mental health. Those with little or no mismatch were less likely to break up over time. These patterns make desired closeness relevant; they do not show that changing a score causes improvement or predict a particular couple’s future.

There is a meaningful counterpoint. The 2022 paper reviews earlier findings in which greater IOS closeness was associated with better relationship quality. A sense of shared identity and intimacy can matter. The narrower conclusion is that amount alone gives an incomplete picture: high closeness can sit alongside a painful mismatch, while different preferred levels may fit each partner well. The couple study was observational and focused on cohabiting US couples, so it cannot set a universal rule or explain why a mismatch exists.

When comparing IOS answers, ask each person: “How close do you feel now?” and “How much closeness would feel right to you?” The second answer frames the first. Desired closeness can include time together and room apart, and that balance may shift as life changes. A difference deserves attention when someone feels repeatedly unmet, but a single gap does not tell you why. Similar scores may conceal different ideals; different scores may coexist with each person feeling met.

Sources: Closeness Discrepancies in Romantic Relationships; The Complicated Connection Between Closeness and the Quality of Romantic Relationships

What IOS validity can say—and what it cannot predict

Validation gives the Inclusion of the Other in the Self Scale authority: it can capture one person's perceived closeness in a compact form. A brief measure can carry meaning when compared with fuller measures of the same idea. But a sound closeness measure doesn't become a diagnosis, a measure of commitment, or a forecast for one couple. In “Measuring the Closeness of Relationships: A Comprehensive Evaluation of the ‘Inclusion of the Other in the Self’ Scale,” researchers tested the IOS in three online studies with 772 adults living in the United States. Participants selected one of seven pairs of circles to represent their relationship with a specific person. The researchers compared those choices with six other scales designed to assess relationship closeness. The IOS correlated positively with each, and the authors concluded that it was a psychologically meaningful and reliable measure of subjective closeness. This supports treating a person's answer as a report of perceived closeness. The comparison also shows why validity has a boundary. One benchmark, the Relationship Closeness Inventory, asks about dimensions such as how often people interact, how many activities they share, and how strongly one affects the other's plans and choices. The IOS takes less than a minute; the inventory takes much longer. Their relationship gives the simple picture credibility as an indicator of closeness, but it doesn't make it a summary of every behavior, intention, or future decision. A short measure answers a smaller question. A later study, “Introducing IOS11 as an extended interactive version of the ‘Inclusion of Other in the Self’ scale to estimate relationship closeness,” tested a version with eleven levels of circle overlap. In an analysis involving 751 people, IOS11 correlated with features of closeness captured by more complex survey instruments. It performed better than the original IOS, about as well as the two-item Oneness measure. This compares measurement formats against other closeness measures. It doesn't show that extra response choices reveal whether partners care equally, or predict what a particular couple will choose next. The same study points to unanswered work: IOS11 still needs study of agreement between a person's report and their partner's, and its ability to predict meaningful behavior. Evidence that one person's IOS answer tracks other measures of perceived closeness isn't evidence that two people experience a bond in the same way. Nor does either finding tell us whether both partners feel free to choose, respond, or repair a strain. Use the IOS for what its evidence supports. Treat a chosen circle as an opening into one person's experience, not a verdict on the couple. Compare two answers as two reports, then ask what each person wants and is willing to build in ordinary life. Mutuality and a shared future emerge through conversation and lived choices. The scale can begin that inquiry; it can't finish it.

Sources: Inclusion of Other in the Self Scale; Measuring the Closeness of Relationships: A Comprehensive Evaluation of the ‘Inclusion of the Other in the Self’ Scale; Introducing IOS11 as an extended interactive version of the ‘Inclusion of Other in the Self’ scale to estimate relationship closeness

How responsiveness becomes visible in ordinary moments

Mutual participation shows itself in what happens after one person reaches for the other. A partner shares a worry, asks for help, or says, “I miss spending time together.” The person must feel understood, taken seriously, and cared for. Both partners can answer, make room for each other’s needs, and return when the first attempt falls short. Responsiveness is a process, not a tally of favors. A grand gesture may feel powerful, yet mutuality appears in repeated moments when each person speaks and responds. The study “Perceived Partner Responsiveness Forecasts Behavioral Intimacy as Measured by Affectionate Touch” examined one small part of that process. A preliminary analysis combined four datasets from 412 couples (824 people). Higher perceived responsiveness was associated with more frequent affectionate touch, even after the researchers accounted for sexual intercourse. Prospective studies, including daily reports and a laboratory task, examined whether responsiveness came before affectionate touch. One study followed 80 couples’ daily reports for two weeks; another collected reports from both partners over 28 days. Across the studies, perceived responsiveness was linked with more affectionate touch, and one study found that a person’s affectionate touch forecast their partner’s next-day perception of the toucher as responsive. This suggests how feeling cared for may connect with an action that communicates fondness. It does not prove that touch causes care, or that every caring partner expresses affection physically. The authors describe the evidence as correlational, and touch is only one possible form of connection. Listening, practical help, or time together may carry that meaning for others. This is why a matching pair of Inclusion of the Other in the Self answers cannot settle whether a bond is mutual. It records felt closeness, not how either person responds when the other reaches out. “Eliciting Short-Term Closeness in Couple Relationships With Ecological Momentary Interventions” also describes the IOS as a broad measure of subjectively experienced closeness, while noting that evidence for its ability to capture behavioral interdependence is mixed. Consider an imagined connection that feels charged with recognition and shared meaning, but where one person repeatedly makes the plans, raises hard questions, and tries to repair distance. The feeling may be real, but participation remains a separate question. A quieter connection may feel less consuming, yet both people listen, adapt, and come back after a misunderstanding. That pattern offers other evidence of mutual involvement, though it cannot prove a relationship’s future. So use the circles as a prompt, then ask about the moments around them. When one of you made a bid for closeness, what happened next? Did the response feel freely offered and received as care? Could both of you name a need, adjust, and return when something went wrong? Look for a pattern. Matching answers may open the conversation; different answers may make it more useful. Neither replaces what each person says and chooses over time.

Sources: Perceived Partner Responsiveness Forecasts Behavioral Intimacy as Measured by Affectionate Touch; Eliciting Short-Term Closeness in Couple Relationships With Ecological Momentary Interventions

Why matching answers can still conceal an uneven bond

Two people can choose the same circles and still be living different versions of the relationship. Matching answers show similar reported closeness at that moment, not equal care or effort, or the same meaning for both. The Inclusion of the Other in the Self Scale asks each respondent to select one of seven circle pairs that best describes their relationship with a particular person. As “Measuring the Closeness of Relationships: A Comprehensive Evaluation of the ‘Inclusion of the Other in the Self’ Scale” explains, the item captures the respondent’s own subjective perception and stays neutral about why they feel close. The answer is useful, but its meaning stays open. Imagine two partners both select the pair with nearly complete overlap. One chooses it because they feel listened to, included in decisions, and able to bring their whole self to the relationship. The other chooses it because the relationship feels secure and familiar, even though they rarely ask what their partner needs. The pictures match; the reasons may not. This illustrates what one answer cannot distinguish. It is not a finding that matching IOS answers conceal unequal effort. The scale does not ask who initiates repair, whose plans make room for the other, or whether both feel free to speak. Now imagine two people who choose a middle pair. One wants intimacy to grow slowly and feels content with the current space. The other also selects that pair, but wishes for more openness and shared time and has stopped asking for it. Their answers agree while their satisfaction may not. In “The Complicated Connection Between Closeness and the Quality of Romantic Relationships,” researchers studied 103 cohabiting US couples and asked each partner about actual and ideal closeness. A person’s actual-to-ideal gap was associated with poorer relationship quality; the partners’ difference in actual closeness alone was not meaningfully associated with quality in the model. The observational study cannot settle what every couple’s matching answers mean. It does show why agreement is not the same as knowing whether each person feels met. A meaningful bond may feel familiar or spiritually resonant. That recognition deserves room in your story, but it cannot answer for your partner. Participation appears in what each person freely says, chooses, and sustains: whether both can name needs, welcome or decline closeness, and return to repair after hurt. These aren't IOS scores. They are the lived context the picture leaves out. So don't stop at “we picked the same circles.” Ask what each answer means, whether the closeness feels right to each of you, and whether both people can shape the relationship. A matching picture can open that conversation. It cannot replace it.

Sources: Measuring the Closeness of Relationships: A Comprehensive Evaluation of the ‘Inclusion of the Other in the Self’ Scale; The Complicated Connection Between Closeness and the Quality of Romantic Relationships

When a difference deserves care rather than a verdict

A difference between two IOS answers deserves curiosity before it deserves a verdict. It may reflect different preferred rhythms of closeness, a demanding week, or a need one partner has not yet put into words. The circles show each person's reported experience; they don't explain its cause. The study The Complicated Connection Between Closeness and the Quality of Romantic Relationships makes a useful distinction here: among 103 cohabiting US couples, researchers found that a person's distance between actual and desired closeness was associated with poorer relationship quality for that person and their partner. The partners' difference in actual closeness, by itself, was not associated with relationship quality in their model. This was an observational study of a particular sample, not a rule that every mismatch is harmless or every relationship should feel the same. So start with the meaning of the difference, then ask whether it can be discussed. Imagine one partner wants more shared time while the other needs quiet evenings after work. If both can describe those needs, make room for each other, and revisit an arrangement that leaves one feeling lonely, the difference may be a preference to negotiate. Agreement need not mean identical desires. It can mean that neither person's need is treated as the only one that counts. The concern changes when the pattern repeats: one person raises a need, the other dismisses it, and only the first keeps adapting. A single circle gap cannot establish that pattern. Nor can a difficult week tell you what the relationship is like across ordinary weeks. Look instead at what happens over time and after a rupture: can each person name what hurt, listen to the answer, and take part in repair? That reflection doesn't turn behavior into another IOS score. It gives you lived context the picture cannot contain. Research on responsiveness offers a reason to notice those exchanges. Perceived Partner Responsiveness Forecasts Behavioral Intimacy as Measured by Affectionate Touch reports links between feeling understood, validated, and cared for by a partner and affectionate touch across its studies. The authors describe correlational evidence, so it doesn't prove that responsiveness caused the touch, or that touch is required in every bond. Its narrower use here is to direct attention toward how partners respond to one another, not to prescribe one form of affection. If you keep feeling unseen, take that experience seriously without asking a scale to prove it. Name the repeated moment and ask whether both of you are willing to respond and repair. A difference becomes meaningful through what the two of you do with it.

Sources: The Complicated Connection Between Closeness and the Quality of Romantic Relationships; Perceived Partner Responsiveness Forecasts Behavioral Intimacy as Measured by Affectionate Touch

Use the two answers to begin one honest conversation

If both partners want to compare answers, begin privately and voluntarily. Each person can choose the circle that reflects their closeness with the same partner, then compare without trying to match. The Inclusion of the Other in the Self Scale describes one person’s perceived closeness; its seven images do not reveal what the other feels. The study ‘Measuring the Closeness of Relationships: A Comprehensive Evaluation of the Inclusion of the Other in the Self Scale’ evaluates individual perception, not shared effort. Then ask what each answer means, whether the closeness feels like the amount each person wants, and what both are willing to sustain. Try: “What does this picture capture for you, what amount of closeness feels right now, and what is one thing we both want to do to make room for it?” Either person can decline. The aim isn’t to persuade someone to choose a closer picture, but to hear an honest answer and see whether words lead to mutual choices and repair over time. ‘The Complicated Connection Between Closeness and the Quality of Romantic Relationships’ distinguishes partners’ actual closeness from each person’s desired closeness; neither comparison alone establishes commitment or predicts a particular future. A Connection Reflection Report can help you consider recognition, mutual participation, repair, and a shared future. The circles can name an experience.

Sources: Measuring the Closeness of Relationships: A Comprehensive Evaluation of the ‘Inclusion of the Other in the Self’ Scale; The Complicated Connection Between Closeness and the Quality of Romantic Relationships

A little more clarity